New supernova analysis reframes dark energy debate

September 13, 2017, Royal Astronomical Society
The difference in the magnitudes of supernovae in the ΛCDM and Timescape cosmologies and the magnitudes the supernovae would appear to have in an empty universe (horizontal dashed line). Both models show recent apparent acceleration following earlier deceleration. In the Timescape model this is not a real effect, however, and the curve is flatter than the ΛCDM case. Credit: Lawrence Dam, Asta Heinesen and David Wiltshire

The accelerating expansion of the Universe may not be real, but could just be an apparent effect, according to new research published in the journal Monthly Notices of the Royal Astronomical Society. The new study—by a group at the University of Canterbury in Christchurch, New Zealand—finds the fit of Type Ia supernovae to a model universe with no dark energy to be very slightly better than the fit to the standard dark energy model.

Dark is usually assumed to form roughly 70% of the present material content of the Universe. However, this mysterious quantity is essentially a place-holder for unknown physics.

Current models of the Universe require this term to explain the observed acceleration in the rate at which the Universe is expanding. Scientists base this conclusion on measurements of the distances to supernova explosions in distant galaxies, which appear to be farther away than they should be if the Universe's were not accelerating.

However, just how statistically significant this signature of cosmic acceleration is has been hotly debated in the past year. The previous debate pitted the standard Lambda Cold Dark Matter (ΛCDM) cosmology against an empty universe whose expansion neither accelerates nor decelerates. Both of these models though assume a simplified 100 year old cosmic expansion law—Friedmann's equation.

Friedmann's equation assumes an expansion identical to that of a featureless soup, with no complicating structure. However, the present Universe actually contains a complex cosmic web of galaxy clusters in sheets and filaments that surround and thread vast empty voids.

This is a computer-simulated image depicting one possible scenario of how light sources are distributed in the cosmic web. Credit: Andrew Pontzen and Fabio Governato / Wikimedia Commons (CC BY 2.0)

Prof David Wiltshire, who led the study from the University of Canterbury in Christchurch, said, "The past debate missed an essential point; if dark energy does not exist then a likely alternative is that the average expansion law does not follow Friedmann's equation."

Rather than comparing the standard ΛCDM cosmological with an empty , the new study compares the fit of supernova data in ΛCDM to a different model, called the 'timescape cosmology'. This has no dark energy. Instead, clocks carried by observers in galaxies differ from the clock that best describes average expansion once the lumpiness of structure in the Universe becomes significant. Whether or not one infers accelerating expansion then depends crucially on the clock used.

The timescape cosmology was found to give a slightly better fit to the largest supernova data catalogue than the ΛCDM cosmology. Unfortunately the statistical evidence is not yet strong enough to rule definitively in favour of one model or the other, but future missions such as the European Space Agency's Euclid satellite will have the power to distinguish between the standard cosmology and other models, and help scientists to decide whether dark energy is real or not.

Deciding that not only requires more data, but also better understanding properties of supernovae which currently limit the precision with which they can be used to measure distances. On that score, the new study shows significant unexpected effects which are missed if only one expansion law is applied. Consequently, even as a toy model the timescape provides a powerful tool to test our current understanding, and casts new light on our most profound cosmic questions.

Explore further: Can we ditch dark energy by better understanding general relativity?

More information: Lawrence H. Dam et al, Apparent cosmic acceleration from type Ia supernovae, Monthly Notices of the Royal Astronomical Society (2017). DOI: 10.1093/mnras/stx1858

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dnatwork
2.1 / 5 (14) Sep 13, 2017
I commented a couple weeks ago with the idea that dark energy (and dark matter) need not exist if the theory took the frame of reference as a real thing to be accounted for, not just an analogy to explain things near the speed of light. This article is basically what I meant; they are talking about the clocks, but of course, the speed of your clock depends on your frame of reference.

I was also thinking gravity is not a real force, but an emergent effect, just inertia in another form. We'll see.
Parsec
4.1 / 5 (8) Sep 13, 2017
The principle of Occam's Razor favors the model without cosmological acceleration.
Hyperfuzzy
1.4 / 5 (9) Sep 13, 2017
First, you are looking at it all wrong. Space is infinite in time and physical dimension. Charge is infinite from it's center to infinity. The motion of a charge's center produces a wave in its field, no other field affected only another's center may be affected, effected, whatever ... This describes space as it is, not how you are calculating. Light, or a wrinkle in its field ... all that exists. There is no "thing" called mass but a "mass" of these centers!

Get it? These fields are everywhere, there does not exist "Nothing!". So yes, your dark mattter is created by assuming "Nothing" really exist. LOL! So from a distance, how may any wavelet be perceived? Forward, backward? Also from within an atom and within greater and greater numbers ... does attraction always win? Note: These centers only obey the law; there is no law defining any configuration other than the applied field or lack thereof. So each center may occupy the same point in space and time.
Hyperfuzzy
1.5 / 5 (8) Sep 13, 2017
Hope you guys are not using QM and GR. You know that's nonsense, mostly. Good try, start with potential and kinectics into a wave equation, compute theorectical possibilities, evaluate reality with this?

Speed of light? Come on! Emitted_wavelength/Measured_Period, what is that? Velocity(+/-)?
oxivape
Sep 13, 2017
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oxivape
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oxivape
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oxivape
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oxivape
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oxivape
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oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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Whydening Gyre
4.2 / 5 (5) Sep 13, 2017
FTA;
"Dark energy is usually assumed to form roughly 70% of the present material content of the Universe."
So, since when did dark energy become "material"?!?

oxivape
Sep 13, 2017
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Benni
1.3 / 5 (11) Sep 13, 2017
Schneibo is now oxivape.

why 1 star me?
Schneibo, for the same reason I always 1 star you.
oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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Da Schneib
4.5 / 5 (10) Sep 13, 2017
@dnat, I assume you're talking about this thread: https://phys.org/...rgy.html

I note that it is still open for comment. I note that you did not respond to my posts. It was an interesting conversation but in the absence of any response from you I think I showed that gravity is a "real thing," not an analogy. We can continue here or there, your pleasure.

Meanwhile, I don't understand why you think the timescape model of Smale et al. is anything like saying gravity is not real, and is an analogy. Can you explain that in a bit more detail for us please?
oxivape
Sep 13, 2017
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Benni
1.3 / 5 (11) Sep 13, 2017
Is no one around?


You should be conversing with the guy right above you, schneibo, he's one of those s'plainers.
oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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Da Schneib
4.5 / 5 (11) Sep 13, 2017
The principle of Occam's Razor favors the model without cosmological acceleration.
But it doesn't explain the supernova data, which means a model without cosmological acceleration doesn't fit reality. Occam's Razor doesn't work if the models it's being used on don't fit reality well. In other words, if you shave too close. ;)
Benni
1.5 / 5 (13) Sep 13, 2017
Can you explain that in a bit more detail for us please?


Well Schneibo, why don't you try more of that Funny Farm Physics stuff & be more clear as to why gravity is DENSITY DEPENDENT & not MASS DEPENDENT.

Explain the Law of Physics that demonstrates how a given mass can change it's gravity field to the point that a given mass stellar body can be made so small that it's gravity field at the surface reaches infinity,
oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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Benni
1.7 / 5 (12) Sep 13, 2017
i got banned from all science forums long ago. only can talk science at glp. now they banned me again, even i use new ip. this is the new place/only one i can learn science.

before i get benned , please talk with me!


oxi......please don't despair, Schneibo is now on site & will converse with you. At he moment he's a little busy on some other Funny Farm explanations of science, but I guarantee he'll be along he will be here for you & to be your friend, you seem just like his type of guy.
oxivape
Sep 13, 2017
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Da Schneib
5 / 5 (8) Sep 13, 2017
Here is the arXiv open access copy of this paper: https://phys.org/...rgy.html

There is a very active debate going on right now about dark energy, regarding whether the presumption of the overall FLRW evenness applies in a non-homogeneous universe like ours, with voids and filaments. This paper provides some evidence using lately collected data. It will be interesting to see how this falls out when all is said and done.
oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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oxivape
Sep 13, 2017
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oxivape
Sep 14, 2017
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kjung6921
5 / 5 (11) Sep 14, 2017
Aren't there any moderators on this site? Too bad. It's a great site with great articles and the comment section (at least at the end of this article where I hoped to find some intelligent discussion of this latest news on the dark energy front) is literally the drooling ward in One Flew Over the Cuckoo's Nest.

Very sad. Very sad indeed. Does anyone know where physics students meet to discuss these things, where moderators kick out the dingbats?

Just curious.
oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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Eikka
3.6 / 5 (7) Sep 14, 2017
maybe they agreed with my comment.

can you debunk any? please!

i want to learn better theory.


A famous university professor went to a monastery to hear about zen. The abbot of the monastery agreed to meet him for tea. Once the professor was seated, the master poured tea into a cup, slowly filling it to the brim until tea was spilling to the table and onto the floor.

"Enough, the cup is full!", said the professor.

"You are like this cup, so full of opinions and ideas. How can I tell you of zen if you don't first empty your cup? Come back when your cup is empty.", said the teacher.
oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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wduckss
1 / 5 (3) Sep 14, 2017
@oxivape
I'll add a little proof about manipulation with readers.
http://www.svemir...-correct
Still, part "force is proportional to sun's temperature and mass, inversely proportional to distance squared". Not true, the temperature on the dark side of Mars is more than the Moon and the Mercury.
oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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ViperSRT3g
3 / 5 (2) Sep 14, 2017
I'm still wondering if this will eventually be explained with the universe was expanding faster in the past, and so because we're seeing things not as they are now, but as they were, they appear to be moving away from us at a much greater speed than objects closer to us in time and space.
oxivape
Sep 14, 2017
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Hyperfuzzy
1 / 5 (4) Sep 14, 2017
Finally, measure the speed of light this way emitted_wavelength/measured_period. Now, the way I see it, we do not have enough information to determine the flow of our local universe, let alone the entire bucket of worms.

If you notice, attraction trumps repulsion, i.e. unlike charges will tend to be closer together than like charges; thus, the supperposition of each charge center will be like-wise! But, think you need a few more vector quantities. If you go with Einstein, bets are off you will ever enter space!
oxivape
Sep 14, 2017
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Hyperfuzzy
1 / 5 (3) Sep 14, 2017
So I would expect something bigger than I've ever seen that can control the flow of galaxies, juz say'n The expansion from us? We're all in a stream, acclerating? Well, first which galaxies are moving away and in what direction are they moving relative to us. Be esiear if you let a computer tell you what is really going on than these guys who say, "I don't know, Dark Matter?" LOL

if it is a stream it can be a supposition of 3 points, us centered; therefore, verifiable data, ...
Hyperfuzzy
1 / 5 (3) Sep 14, 2017
Anyway, the stream shall define an unseen object! Not something that we do not know exist and what it is, a real object!

So, looking at the distances, we got time! But don't know about life on earth.
Hyperfuzzy
1 / 5 (3) Sep 14, 2017
Your eyes, you see a light, did the plane wave move over you front to back or back to front. In other words, can you update each wavelet as a time sequence, forward or backward. I'm afraid, you will be required to know exactly what you are observing and can absolutely define the time line. Just when you thought this was getting to be really fun, isolated objects in space, of stable sizes, may have which rotators? Either!!! Anti-Matter?
Hyperfuzzy
1 / 5 (3) Sep 14, 2017
Being a member of a stream and an isolated object; what would be the observable differences? Remember, we are new to this world; I think we get only one shot at getting it correctly speaking, i.e. it better be right!
Hyperfuzzy
1 / 5 (3) Sep 14, 2017
We quote PhD's, that's because, some of these actually measure nature and collect knowledge; like Maxwell; others invent knowledge. I fly upon the wings of Maxwell and those who provided the data that properly defines knowledge!
oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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Hyperfuzzy
1 / 5 (3) Sep 14, 2017
the mechanism of electromagnetism is simple, the force f=Ke x e1e2/rr between matters is the carrier of electromagnetism.

there is no field but force between two parallel copper wires at distance r. the repulsion force between electrons on the surface of the two wires. f=Ke x e1e2/rr.

if electrons move/accelerate in one wire, that repulsion force between electrons on the two wires will move/accelerate electrons in the other wire. the mechanism of electromagnetism.

there is no field, only electrostatic force at work.

Lay off the pipe, dude. Or just mellow out, think, don't write $hit! You are repeating $hit, what is it you know about "that will add knowledge or change perspective?"
Hyperfuzzy
1 / 5 (2) Sep 14, 2017
OK, study Maxwell, see the "understood" axioms? What is charge? Therefore ... Not about new physics. It was stated that at the turn of the century(20th), we knew everything! Black Body radiation? Really? Sounds more like data not well understood, what is a black body? Really, we know the physics, ...
oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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antialias_physorg
5 / 5 (7) Sep 14, 2017
wonder how many times they tried to ban me?

People are keeping count Zeph. Don't you worry your pretty littel head

...and they will ban you this time, too.
Hyperfuzzy
1 / 5 (2) Sep 14, 2017
if i am a blind, i never see my face. i touch my face, i imagine my face, listen to people telling me about my face all my life.

i day by chance, a traveling magician meet me and opened my eyes.

what should i repay?

if i look into the mirror, find a monkey.

should i hate the magician? science knowledge is the face of my mind.

tptb nailed a magician 2000 years ago. remember? i love my pipe.

You know, that makes no sense. Everything is what it is! So maybe you prefer blinders?
oxivape
Sep 14, 2017
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oxivape
Sep 14, 2017
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antialias_physorg
5 / 5 (8) Sep 14, 2017
Whops...that worked fast. Thanks mods!
ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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Reg Mundy
1.2 / 5 (6) Sep 14, 2017
@dnatwork
I commented a couple weeks ago with the idea that dark energy (and dark matter) need not exist if the theory took the frame of reference as a real thing to be accounted for, not just an analogy to explain things near the speed of light. This article is basically what I meant; they are talking about the clocks, but of course, the speed of your clock depends on your frame of reference.

I was also thinking gravity is not a real force, but an emergent effect, just inertia in another form. We'll see.

Congratulations, you have seen the light.
ciggenie
Sep 14, 2017
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Da Schneib
4.5 / 5 (8) Sep 14, 2017
Persistent, isn't he, our Zeph,
antialias_physorg
4.6 / 5 (9) Sep 14, 2017
Persistent, isn't he, our Zeph,

He likes to type for the circular file.
(and I guess he hasn't figured out that non one is reading his walls of text anyways.)

Oh, well...one more crazy kept off the street.
ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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Reg Mundy
2.6 / 5 (10) Sep 14, 2017
@moderators
Howz about stopping anybody from posting more than, say, three times on any thread? The idiots have ruined this interesting and perfectly good discussion...
ciggenie
Sep 14, 2017
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Benni
1.4 / 5 (10) Sep 14, 2017
@moderators
Howz about stopping anybody from posting more than, say, three times on any thread? The idiots have ruined this interesting and perfectly good discussion...


Then Schneibo wouldn't be able to push his DENSITY DEPENDENT theories of gravity versus the demonstrable Fundamental laws of Physics that gravity is MASS DEPENDENT.

So be careful what you wish for, it may only result in a tradeoff of one kind of a fruitcake for another.
dnatwork
2.4 / 5 (8) Sep 14, 2017
@dnat, I assume you're talking about this thread: https://phys.org/...rgy.html

I note that it is still open for comment. I note that you did not respond to my posts. It was an interesting conversation but in the absence of any response from you I think I showed that gravity is a "real thing," not an analogy. We can continue here or there, your pleasure.

Meanwhile, I don't understand why you think the timescape model of Smale et al. is anything like saying gravity is not real, and is an analogy. Can you explain that in a bit more detail for us please?

I didn't say this article said anything about gravity being an effect rather than real, just that that was the other thing I said two weeks ago. I was not convinced by your statements, but I don't have the math to support my intuition, so I dropped it.
dnatwork
2 / 5 (8) Sep 14, 2017
Anyway, if the light we observe had to pass through billions of years and quadrillion's of miles of space, it must have passed through many different reference frames, all of which are different from ours. Moreover, either the universe was expanding throughout that time, or the space around every bit of mass was collapsing in on itself, but either way everything was getting farther apart. These guys had the math and the knowledge to point out that therefore it is not valid to assume the Friedman law is correct, that space is flat or whatever. It would have to be tested and proven instead.

If that's true, then what other assumptions in the standard model are untested and unproven? Yes, your equations produce the correct results for the perihelion of Mercury. Does that mean there are no other equations that could do the same? Or that every assumption in the model is correct? No, and no.
dnatwork
2 / 5 (8) Sep 14, 2017
So if I say "gravity might just be inertia in curved space, not any kind of force at all," and you say "the standard model explains all this so gravity is a real force, but our theory leads us to have no clue what 95% of the universe is" well, I'm not going to be convinced. And that was before these guys pointed out the weakness of the assumptions on flat space. It just didn't pass any sniff test.
dnatwork
2 / 5 (8) Sep 14, 2017
I'm actually arguing for most of the standard model to be kept, I just think it's overbuilt. Take away a few things, but don't replace them with anything. No gravity, because inertia does all the work you need if you let it follow the curves of spacetime. No dark energy or dark matter, because changing reference frames do all the work you need if you let spacetime warp and stretch in different ways (but always according to the same laws applied in differing environments) throughout space and time. Derive those effects from first principles, don't assume they are laws.

I don't know what else might be pruned, but any model that forces you to weird conclusions needs to be cut back until it matches the facts.
ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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fthompson495
1 / 5 (2) Sep 14, 2017
We are in the outflow of a Universal black hole. As ordinary matter falls toward the Universal black hole it evaporates into dark matter. It is the dark matter outflow which pushes the galaxy clusters, causing them to move outward and away from us. The dark matter outflow is dark energy.
kjung6921
5 / 5 (4) Sep 14, 2017
"The accelerating expansion of the Universe may not be real..."

The biggest NEVER MIND in the history of science (following the extreme upheavals to cosmology, astronomy and physics that the 1998 discovery of accelerating expansion brought).

And what about the 3 Nobel Prizes awarded to participants in that discovery? Do they have to now be returned.

The fact that the posted article doesn't even mention what a revolution in astronomy they would be effecting if their claim that the acceleration is "could just be an apparent effect" is proved leads me to believe there's not much there here.

I am extremely skeptical. The acceleration was discovered nearly 20 years ago. It was corroborated in 2011 by another mammoth study of millions of galaxies.

And now today it's what? All nothing? Mirage? Never mind?

Color me extremely skeptical. This is the scientific-world's equivalent of click-bait, or grant-bait.

ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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kjung6921
5 / 5 (7) Sep 14, 2017
Google this: "No, Astronomers Haven't Decided Dark Energy is Nonexistent"

It's in Scientific American and it answers a previous "reframing" attempted in 2016.

ciggenie
Sep 14, 2017
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kjung6921
4.3 / 5 (6) Sep 14, 2017

the sun's energy/vibrating electrostatic force/radiation ... produces earth magnetic field, causes polar lights.


You really don't know that the Earth's magnetic field is produced in the Earth's core? What grade are you in? Your elementary school science teachers should be ashamed of your ignorance.

Da Schneib
4.3 / 5 (6) Sep 14, 2017
Somehow my link to the open access arXiv paper got munged above, and with @Zeph hammering the thread I didn't notice. The correct link is: https://arxiv.org...06.07236
ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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Da Schneib
4.3 / 5 (6) Sep 14, 2017
@kjung, Yes, I read that SciAm post. I am still reading the paper this article is about, and thinking about the objections raised against DE. There is no question whether there is an effect. The sticking point is and always has been that we simply don't know what it is.

The particular study in the current paper proposes that this effect is due to a difference in the way redshift happens in voids as opposed to the way it happens in filaments (the authors talk about "walls," but if you look at the plots they show, it's apparent they have at least some evidence that a large portion of our sky looks into large voids).

Like you I am skeptical; the standard interpretation of GRT says that voids cannot cause a blueshift in light, and mass concentrations cannot cause a redshift, in sufficient quantity to account for the redshift we see. Wiltshire et al. claim they can. The evidence is equivocal at this point (though it leans 99% against the Wiltshire claim).
ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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Da Schneib
4.5 / 5 (8) Sep 14, 2017
@Zeph so you know I reported one of your posts. I expect you'll be out of here when the mods come back on line.

I don't know why you bother. Did you get kicked off another science site?
Da Schneib
4.3 / 5 (6) Sep 14, 2017
@dnat I saw your posts. I'll try to respond today, work permitting. Short form, all the void proposals are extensions to GRT to try to account for Lambda on the RHS of the EFE despite claims to the contrary. It's OK to claim redshift for entry into the filaments, but to flesh these out these folks pretty much always require non-GRT to introduce blueshifts into voids; that is, really nothing doing something. I am very skeptical.
ciggenie
Sep 14, 2017
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Hyperfuzzy
5 / 5 (1) Sep 14, 2017
what is time?

if we put the same clock in the sun and the earth for 1 day

the earth clock will read/run 24 hours, the sun clock will read fewer hours.

which clock is correct? what time is correct time?

we use matters movement to measure time, what we measured is the changing of the movement, the reading on the timer.

all matters, all things are constantly moving, never stop.

time is always moving with all things right now.

past and future only exist in our minds.

a living tree can be a timer

a blooming flower can be a timer

but the tree and the flower are not time

nor the readings on the clock

all the time we/the universe/existence have is ever changing now

WHAT WE BECOME IS THE MATTER

Prove it, do it!
ciggenie
Sep 14, 2017
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Tuxford
1 / 5 (4) Sep 14, 2017
The principle of Occam's Razor favors the model without cosmological acceleration.

And tired light over inter-galactic distances explains it rather simply, as LaViolette has pointed out decades ago. But merger mania is forever. What is the maniac going to do now? Squirm?
ciggenie
Sep 14, 2017
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JongDan
3 / 5 (2) Sep 14, 2017
I was also thinking gravity is not a real force, but an emergent effect, just inertia in another form. We'll see.

Dude I hope you're aware that entire general relativity is build upon this idea.
ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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dnatwork
2.7 / 5 (7) Sep 14, 2017
I was also thinking gravity is not a real force, but an emergent effect, just inertia in another form. We'll see.

Dude I hope you're aware that entire general relativity is build upon this idea.


Odd, others have been telling me that contradicts general relativity.

Wikipedia: Phenomena that in classical mechanics are ascribed to the action of the force of gravity (such as free-fall, orbital motion, and spacecraft trajectories), correspond to inertial motion within a curved geometry of spacetime in general relativity; there is no gravitational force deflecting objects from their natural, straight paths. Instead, gravity corresponds to changes in the properties of space and time, which in turn changes the straightest-possible paths that objects will naturally follow.


Huh, sounds like GRT says gravity is not a force, just an effect of inertia in curved spacetime. Good thing I'm just a guy on the internet, reading press releases about science-y stuff.
dnatwork
2.6 / 5 (8) Sep 14, 2017
Okay, then I need to know more before spewing thoughts.

Still thinking dark energy and dark matter look like attempts to pick up the soup after you've dropped the bowl.
ciggenie
Sep 14, 2017
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Hyperfuzzy
3 / 5 (2) Sep 14, 2017
Okay, then I need to know more before spewing thoughts.

Still thinking dark energy and dark matter look like attempts to pick up the soup after you've dropped the bowl.

All you need is an MSEE and common sense!
Da Schneib
4.2 / 5 (5) Sep 14, 2017
@dnat, your point that relativists contend that gravity is not a force is well taken; it rather washes the sand out from under their feet. If this is what you meant by your statement I may not have an argument against it, but I don't agree that this is an argument against dark energy, and it certainly isn't an argument against dark matter.

I'll show why when I have a chance to think about this, and post soon. Thanks for your patience.
ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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Whydening Gyre
4.5 / 5 (8) Sep 14, 2017
@Zeph so you know I reported one of your posts. I expect you'll be out of here when the mods come back on line.

I don't know why you bother. Did you get kicked off another science site?

DS, I don't think cigg is Zeph. Not his writing and posting style.
Neither was the Oxivape one
this one is more like Hyper's Uncle or something...
ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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Benni
1 / 5 (9) Sep 14, 2017
this is serious matter, no one gives a fuck? what's wrong with you people?


@ciggenie...........Have you yet met Schneibo? He sometimes goes by Da Schneib. You have become a good match for him when it comes to serial posting, I swear he sometimes becomes out of breath blue from the arduous exercise he puts those fingers through, exhausting stuff talking about nothing or Copy & Pasting other people's stuff.

But hey guy, don't worry, he's been here for a few years posting the same slop & swill over & over again, so you should be OK, I won't give you any ones, I'll just continue reserving those for copycat Schneibo.

Oh, one thing missing if you imagine you want to compete with Schneibo, you need to upgrade your name calling & foul mouthed profanity skills, that would easily tack another 50 points onto your IQ, Schneibo learned that shortcut almost right off the bat, he gets up to grade school level of science from time to time.
ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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ciggenie
Sep 14, 2017
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Hyperfuzzy
3.7 / 5 (3) Sep 14, 2017
As we mumble and seek approval of what is published due to [ Publish or perish ] does not define truth! Truth is, wither you believe it, can explain it, understand it, it is!

So, kudos to those who observe! Then ...
ciggenie
Sep 14, 2017
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Maggnus
5 / 5 (10) Sep 14, 2017
@ciggenie...........Have you yet met Schneibo? He sometimes goes by Da Schneib. You have become a good match for him when it comes to serial posting, I swear he sometimes becomes out of breath blue from the arduous exercise he puts those fingers through, exhausting stuff talking about nothing or Copy & Pasting other people's stuff.

But hey guy, don't worry, he's been here for a few years posting the same slop & swill over & over again, so you should be OK, I won't give you any ones, I'll just continue reserving those for copycat Schneibo.

Oh, one thing missing if you imagine you want to compete with Schneibo, you need to upgrade your name calling & foul mouthed profanity skills, that would easily tack another 50 points onto your IQ, Schneibo learned that shortcut almost right off the bat, he gets up to grade school level of science from time to time.


I removed yu from ignore this one time to say this:

You are a fucking moron.
ciggenie
Sep 15, 2017
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ciggenie
Sep 15, 2017
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ciggenie
Sep 15, 2017
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Ojorf
4.3 / 5 (6) Sep 15, 2017
Finally!
Something I agree with.

Anyway, about the article, I'm also somewhat skeptical, will have to see how it pans out.
Just a point, if this study is correct, it does not mean the universe is NOT expanding, it means expansion is not accelerating.
Expansion due to BB & inflation still applies.
ciggenie
Sep 15, 2017
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nikola_milovic_378
Sep 15, 2017
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antialias_physorg
4.4 / 5 (7) Sep 15, 2017
And he's back....and he's gone (soon-ish)
dnatwork
2.2 / 5 (6) Sep 15, 2017
@dnat, your point that relativists contend that gravity is not a force is well taken; it rather washes the sand out from under their feet. If this is what you meant by your statement I may not have an argument against it, but I don't agree that this is an argument against dark energy, and it certainly isn't an argument against dark matter.

I'll show why when I have a chance to think about this, and post soon. Thanks for your patience.


Hey, thanks for continuing to be serious and respectful of me as a person, despite my ignorance.

My disagreement with (A) dark energy and dark matter is not dependent on (B) the idea that gravity is not a force, just inertia in curved spacetime.

Rather, I'm starting from the rubber sheet analogy of gravity wells. How real is that image in the theory? Does the theory hold that, like the rubber sheet, the gravity well of a massive object reaches a certain point and then stops?
dnatwork
1.8 / 5 (5) Sep 15, 2017
cont'd.

If it stops at a certain degree of curvature, what stops it? Is there a countervailing force pushing up (I don't know, vacuum energy?)? Does space itself have structure or stiffness that must be overcome by the mass to induce the curvature?

If yes, where is that force or structure expressed in the theory? Is it explicit, or does the theory carry the effects of such a force implicitly? In other words, is the theory based on assumptions that things like Friedmann's equation are true, but no one ever talks about those fundamentals or examines them?

If that is the case, why are those assumptions not examined when you get odd results like "95% of the universe is invisible, and we can't interact with it, but it affects gravity." (Which is doubly odd if gravity is an effect of spacetime being curved by mass, not a force in its own right.)

The authors of this article are questioning that fundamental assumption, so I see that as the same basic question I was asking.
dnatwork
1.8 / 5 (5) Sep 15, 2017
cont'd.

I don't know what this thing they are calling "timescape" is really supposed to mean, but conceptually it seems to have the same effects as my alternative: What if the rubber sheet analogy should not be allowed to be carried into the theory, and the theory should not include anything that pushes back up against mass?

Then spacetime would continue to curve indefinitely around every object, each within its own reference frame. From that, the space between objects would get larger over time, even if they were not "moving" relative to each other, because each would be in a deeper and deeper gravity well. Within each gravity well, no observer would ever find any local effects from this because they are within their own reference frames. The only way to see the deepness of the wells increasing would be to observe distant massive objects over large timescales. The same things that are taken as evidence of dark energy and dark matter.
dnatwork
1.8 / 5 (5) Sep 15, 2017
cont'd.

So when you say you will show me why I'm wrong, I think you will also have to show why these authors are necessarily wrong. But since they are questioning a (hidden) fundamental assumption of LCDM, you'll need to defend all those assumptions first.

Like I said, I'm just a guy without much knowledge, but I think these questions are valid no matter who asks them: What are the assumptions behind the theory, why is any given assumption true, and if it can't be proven true, in what ways might it lead you astray?

Put another way, does the emperor have any clothes, and who is going to speak up if he doesn't?

Pointing me to evidence like the Bullet Cluster just begs the question. That is just an observation, and its import has been disputed by serious and respected physicists. I get it, you must have dark matter to explain it within standard theory. But saying THAT is evidence of dark matter means you are assuming every part of the standard theory was correct.
Da Schneib
3.7 / 5 (6) Sep 15, 2017
Anyway, if the light we observe had to pass through billions of years and quadrillion's of miles of space, it must have passed through many different reference frames, all of which are different from ours.
That's not what a reference frame is. A frame of reference is some place you stand and a coordinate system you define from which you make measurements. Many different frames of reference are possible at the same place to stand, all with different coordinate systems. Many different reference frames are possible at many different places to stand. The point of physics is that it doesn't matter which one you choose, you get the same physics after you apply a transformation (a mathematical operation) to convert between them.

Until we can talk about frames without you thinking they are some part of physical reality other than the particular one you choose to measure relative to, we probably won't make much headway.
Da Schneib
3.9 / 5 (7) Sep 15, 2017
Let me try this again.

When you measure a physical system, you must choose a position and a coordinate system from which you will perform the measurement. This position and coordinate system are part of the measurement, not part of what is measured. This position and coordinate system *you have chosen* are called a "frame of reference."

When Einstein discovered relativity, he pointed a couple of things out.

The first is an *inertial* frame of reference. This is a frame in which an accelerometer would show zero acceleration. The laws of physics are the same from all inertial frames; they can be transformed using the Lorentz Transformation, and no matter which frame you look from you will see the same laws of physics. That does not, however, mean you will see the same events, or even the same order of events!

When we consider light from two different frames, *the energy must be transformed*.
[contd]
Hyperfuzzy
1.8 / 5 (5) Sep 15, 2017
Let me try this again.

When you measure a physical system, you must choose a position and a coordinate system from which you will perform the measurement. This position and coordinate system are part of the measurement, not part of what is measured. This position and coordinate system *you have chosen* are called a "frame of reference."

When Einstein discovered relativity, he pointed a couple of things out.

The first is an *inertial* frame of reference. This is a frame in which an accelerometer would show zero acceleration. The laws of physics are the same from all inertial frames; they can be transformed using the Lorentz Transformation, and no matter which frame you look from you will see the same laws of physics. That does not, however, mean you will see the same events, or even the same order of events!

When we consider light from two different frames, *the energy must be transformed*.
[contd]

Bull$hit!
Da Schneib
4 / 5 (8) Sep 15, 2017
[contd]
Consider two inertial frames with not only different positions and coordinates, but with constant motion. An observer in one frame will see light from a particular source with a particular frequency shift from the frequency in that source's frame of reference; an observer in the other frame will see a different shift. This means that the energy of the light in the first frame is not the same as the energy of the light in the second frame, and furthermore neither is necessarily the same as the energy of the light in the frame of the source. In other words, when switching between frames, the amount of energy is not the same; it must be transformed.

This in turn means that the common notion of light "changing frequency while moving through expanding space" is nonsense. The light does not change frequency in any frame (unless the frame is accelerating, and that gets much more complex; it's the difference between SRT and GRT).
[contd]
Da Schneib
4 / 5 (8) Sep 15, 2017
[contd]
In any one inertial frame of reference, the light *does not change frequency*. (Under GRT it's possible for it to change frequency if the acceleration changes; in other words, if the frame undergoes jerk, but that's a different matter. We can discuss it later if you like.)

Since light moving through open space is not being measured, it doesn't make any sense to speak of its frequency. It only makes sense to speak of its frequency *in a frame*.

In the frame of the source, spectral lines occur at the standard frequencies (in the source's frame) controlled by atomic physics. If the frame of the source and the frame of the observer are moving relative to one another (even if both are inertial), then those frequencies (in the observer's frame) *always were redshifted*. The light wasn't somehow magically changed between the source and the observer. In any one frame, energy is conserved; but when shifting among frames there is no such concept.

[contd]
Da Schneib
4 / 5 (8) Sep 15, 2017
[contd]
Measuring light "in open space" is meaningless. If you measure, you define a frame; if light is emitted, that also defines a frame because of the atomic interactions that generate spectral lines. It's therefore not correct to talk about light "being expanded by spatial expansion between here and there" because no frame of reference has been defined in which this measurement can be made.

Does that clarify the frame of reference thing for you, and explain Hubble redshift? Let's just start with those two.
Da Schneib
4 / 5 (8) Sep 15, 2017
One more way to look at frames:

Suppose I say "object A is moving at 30 m/s." Now we have some questions here:
1. 30 m/s in what direction?
2. 30 m/s relative to what particular place?
3. Is that place moving?
4. Is that place accelerating?

The answers to these questions define a frame a reference: a particular coordinate system defining directions, a "zero" point for those coordinates, a state of motion of that zero point, and a state of acceleration of that zero point. You can't make a measurement without this; but it's completely arbitrary and not part of what you're measuring, but of the measurement itself.

If I pick two points from which to measure with different coordinate systems moving differently from one another with different accelerations then I will get two different answers for how the object is moving.

Those are different frames of reference.
[contd]
Da Schneib
4 / 5 (8) Sep 15, 2017
[contd]
It is obviously incorrect to claim the object is "moving at 30 m/s;" it is only meaningful to say it is "moving at 30 m/s relative to frame one" or "moving at 30 m/s relative to frame two." And that is what frames are, and are for: to define measurements.
dnatwork
1.8 / 5 (5) Sep 15, 2017
[contd]
It is obviously incorrect to claim the object is "moving at 30 m/s;" it is only meaningful to say it is "moving at 30 m/s relative to frame one" or "moving at 30 m/s relative to frame two." And that is what frames are, and are for: to define measurements.


Okay. I think I never said anything about frequency, but the redshift is about that, so let's say I did.

In LCDM, if I understand correctly (a phrase that constantly earns me derision around here), the increase in redshift over time is taken as evidence that the expansion of the universe has been accelerating, and that is where dark energy is postulated to explain the acceleration. Correct?

That would seem to be true if relative motion is the only way to increase the space between objects. The speed of light is constant, so if i move away from the light source I get redshift. I'm postulating an additional way to increase the amount of space over time.
dnatwork
1.8 / 5 (5) Sep 15, 2017
cont'd.

If space is defined by the mass and energy in it, and I have mass A over here and mass B over there, then the space between them is defined by the relation of A and B. Wouldn't that be both the shape of the space and the amount of space?

Now A is sitting in its own space, doing its own thing, and so is B. Each continues to be the source of the definition of its own space, including the depth of its own gravity well.

What stops a gravity well from getting deeper over time? I haven't seen anyone address that yet. Is there something in the theory that sets a limit, or is it assumed somewhere that X amount of mass will produce Y amount of curvature of spacetime, no more, no less?

If one assumes that nothing stops it, then the well of A gets deeper, and the well of B gets deeper, gradually over time. The speed at which each well gets deeper would depend on the amount of each mass.

Benni
1.6 / 5 (7) Sep 15, 2017
That would seem to be true if relative motion is the only way to increase the space between objects. The speed of light is constant, so if i move away from the light source I get redshift. I'm postulating an additional way to increase the amount of space over time.


You just describe Doppler Effect Redshift. The effect being that as objects move away from one another that this increased distance causes light between the two objects to shift to longer wave frequencies of the visible light spectrum, that is a shift to the direction of the red frequency of visible light, but not that all the visible light actually becomes red. If the light between the two objects was originally purple then after a certain distance of constantly increasing distance of travel it means that light will downshift to a blue lower energy wavelength.

Schneibo is doing a lousy job explaining this stuff in terms of reference frames.
dnatwork
1.8 / 5 (5) Sep 15, 2017
cont'd.

So, what happens to the space between A and B? If "gravity wells getting deeper" means anything (you can say it doesn't, but I'm positing that it does), then the space between them would have to be increasing.

Light has to pass through space as defined by matter, along geodesics or whatever. It should have to climb all the way out of one gravity well, then fall all the way into the other. If the distance up and down increased over time, it should take longer for light to travel from A to B now than it did a billion years ago, even if A and B are not moving relative to each other.

And if the distance changed while the light was in transit from A to B (say they're ten billion light-years apart), wouldn't that cause redshift? Not by measuring the light somewhere in empty space, but by virtue of the fact that the speed of light is constant but the distance changed? The normal reason for redshift, in other words, just a different reason for the change in distance.
Hyperfuzzy
2 / 5 (4) Sep 15, 2017
wavelength.

Schneibo is doing a lousy job explaining this stuff in terms of reference frames.

Lambda_emitted * frequency_observed = speed; speed <= infinity; -infinity <= velocity <= infinity; Lambda_Observed <= infinity! The framing as a God is obvious; choose an isomorphic space with each dimesionnal scaled as lambda, duh!
dnatwork
1.8 / 5 (5) Sep 15, 2017
cont'd.

What I'm saying is, you clearly understand the theory and the math better than I do (I address that to da Schneib and Benni equally, even though you seem to hate each other), but if nothing stops mass from drilling its own gravity well "deeper" until the end of time, why doesn't space necessarily increase? Is there some "conservation of space" axiom that I'm missing? Would that be Friedmann's equation?

And if space is not conserved, but instead necessarily increases (because it is the measurement of the distance from the bottom of one gravity well to the bottom of the next, or more accurately the time it takes light to travel from one to the other), why do you need dark energy?
Benni
2 / 5 (8) Sep 15, 2017
(because it is the measurement of the distance from the bottom of one gravity well to the bottom of the next


What do you mean by "gravity well"? I take it you mean any gravitating body no matter how large or small, that to me is a "gravity well".

Gravity Wells are most often used in reference to discussions of black holes where the term "INFINITE GRAVITY WELL" is a frequently used terminology.

What I'm trying to figure out here is how you are trying to connect GRAVITY WELLS together if by other than gravitational attraction.

dnatwork
2.3 / 5 (6) Sep 15, 2017
(because it is the measurement of the distance from the bottom of one gravity well to the bottom of the next


What do you mean by "gravity well"? I take it you mean any gravitating body no matter how large or small, that to me is a "gravity well".

Gravity Wells are most often used in reference to discussions of black holes where the term "INFINITE GRAVITY WELL" is a frequently used terminology.

What I'm trying to figure out here is how you are trying to connect GRAVITY WELLS together if by other than gravitational attraction.



Mass curves spacetime. In the rubber sheet analogy, the gravity well is the bowl created by the mass sitting in the middle of the rubber sheet. Light has to travel on the geodesics of that bowl.

With a black hole, that bowl does down forever, or close enough, as light cannot get out. It is deeper than other gravity wells.

I'm saying all such wells get deeper over time. But the effect of deepening is not more black holes.
dnatwork
2.3 / 5 (6) Sep 15, 2017
Let's say you have a point in space with no mass or energy in it. It is locally flat there.

Now you have mass A and mass B on either side of that empty space. The masses there create gravity wells centered on A and B.

Light traveling from A to B has to follow the geodesic up out of one well to the flat spot in the middle, then back down into the other well. (The passage of the light momentarily curves the "empty" space, but that's not material.)

So if the wells are following rubber sheet physics, they immediately a certain depth and stop, and the space never increases unless A and B are moving relative to each other.

But if there is no rubber sheet, no upward force in the real world, then the wells would each get deeper over time. The curvature of spacetime would be defined not just by the amount of matter and energy in space, but also the amount of time that mass was there. It would be a rate of drilling, not a set well depth.
Da Schneib
4.3 / 5 (6) Sep 15, 2017
It is obviously incorrect to claim the object is "moving at 30 m/s;" it is only meaningful to say it is "moving at 30 m/s relative to frame one" or "moving at 30 m/s relative to frame two." And that is what frames are, and are for: to define measurements.
Okay. I think I never said anything about frequency, but the redshift is about that, so let's say I did.
As soon as you mention redshift you're talking about frequency *and* wavelength (they vary inversely). Redshift is measured by finding the exact frequencies of the spectral lines, indicating the motion of the source. If the source is moving away then there will be redshift; the amount of change in the frequency of the spectral line shows how fast it's moving away. It doesn't matter how or why it's moving away; the only question here is how fast. And the amount of redshift shows that.
[contd]
Da Schneib
4.2 / 5 (5) Sep 15, 2017
[contd]
In LCDM, if I understand correctly (a phrase that constantly earns me derision around here), the increase in redshift over time is taken as evidence that the expansion of the universe has been accelerating, and that is where dark energy is postulated to explain the acceleration. Correct?
No, it's more complicated than that. The amount of redshift increases with distance. This is simply because space is expanding, and because there is more space between us and something farther away. The measure of how velocity increases with distance is called the "Hubble Constant."

LCDM says space isn't just expanding at a constant rate; it's expanding at an accelerating rate. To see this, we have to check how the Hubble Constant varies over time. Now, this seems simple enough but it's really not. Before the supernova data, we didn't have a good way to judge galaxy distance.
[contd]
dnatwork
1.8 / 5 (5) Sep 15, 2017
The effect of the well getting deeper would be that things outside of the well would seem to get farther away over time because the geodesic for light to travel would get deeper.

The effect would have to be very small, or you would see it in local settings. If you shared a well with some other object (stars in your galaxy, galaxies in your local group), or not much time had passed, you would not see it. For massive galaxy groups far away in time and space, it would appear, and its magnitude would be proportional to the time and distance.

I.e., I'm taking the evidence for dark energy as my evidence.

You would also see it when gravity wells got so deep so fast that light couldn't get out. Thus, black holes are not infinite, the space they define is just getting deeper at rate that light cannot overcome. The same exact explanation must necessarily apply to the Hubble distance. Things that far away are in wells that, relative to our own well, are getting deeper too fast.
Da Schneib
4.2 / 5 (5) Sep 15, 2017
[contd]
We used redshift (which is a circular definition you'll immediately notice) and galaxy brightness. Galaxy brightness varies a lot over different galaxies, and we think it varies a lot with the age of the galaxy too. But once we had supernova data, we could find the distances of galaxies a lot more easily.

This in turn allowed us to make a much more accurate plot of distance vs. redshift, that is of the variation of the Hubble Constant over time, and when we did that we found out that starting about 6 billion years ago, the Hubble Constant started increasing. This is what is meant by "accelerating expansion."

The supernova data came in during the 1990s, so this is when people started talking about "dark energy." Now, dark energy is the Lambda, the L, in LCDM. It's not just about expansion; it's about *accelerating* expansion.
[contd]
Da Schneib
4.2 / 5 (5) Sep 15, 2017
[contd]
Notice the Hubble Constant isn't a constant any more. It varies over time; that's LDCM as opposed to the old Big Bang theory. It's not the only difference between them, but you're focusing on dark energy so I'm focusing on Lambda because that's dark energy.

That would seem to be true if relative motion is the only way to increase the space between objects. The speed of light is constant, so if i move away from the light source I get redshift. I'm postulating an additional way to increase the amount of space over time.
No. What this is, is a way to make it increase *faster* over time. That's what acceleration is. What you need the additional way for is to make it do it faster. That's what Lambda is: the acceleration factor. But the space expands the same way.
Da Schneib
4.2 / 5 (5) Sep 15, 2017
If space is defined by the mass and energy in it, and I have mass A over here and mass B over there, then the space between them is defined by the relation of A and B. Wouldn't that be both the shape of the space and the amount of space?

Now A is sitting in its own space, doing its own thing, and so is B. Each continues to be the source of the definition of its own space, including the depth of its own gravity well.
Sure, and there is some gravity between A and B too, which also defines the shape of the space between them.

What stops a gravity well from getting deeper over time? I haven't seen anyone address that yet.
The depth of a gravity well is defined by the amount and density of the matter in it. There isn't any definition other than that, and neither Hubble Constant nor Lambda influences that. If more matter infalls, then the gravity changes, but that's the only way.
[contd]
dnatwork
1.8 / 5 (5) Sep 15, 2017
What's the point?

Dark energy has to comprise most of the universe to explain the accelerating expansion of the universe, but we can only see it by virtue of the fact that space is expanding faster. It is the proof of its own existence, or the theory falls apart.

My deepening gravity wells posit no new structures or matter or energy--gravity wells already exist in standard theory, space exists (whatever it is), light travels at a constant speed, etc.

The difference is that the depth of a gravity well seems to be defined only in space in standard theory:

(if it was spacetime was curved X degrees by mass A at time T, it will also be curved X degrees by mass A at every other time),

but it is defined in both space and time in my little theory:

(at time T+1, spacetime around A will be curved more relative to any locality defined by other masses).

It has to be one or the other. With my version, you get accelerating expansion for free if you believe the rest of GRT.
dnatwork
2.3 / 5 (6) Sep 15, 2017
Doppler Effect Redshift?

there is no wave in space, no medium to carry any waves.

fact or not?


no one wants to answer or what? why? please


Nobody understands your question. That, coming from the guy who understands less than most. It's partly a language barrier.

Do what I do: Assume you know nothing, that all of your assumptions are false, and build up your question from there.
Da Schneib
4.2 / 5 (5) Sep 15, 2017
[contd]
Is there something in the theory that sets a limit, or is it assumed somewhere that X amount of mass will produce Y amount of curvature of spacetime, no more, no less?
Yes, precisely. And since we've never found anything that makes the part of gravity created by mass change, and since mass is conserved, we don't know of anything that will do that. So it's a pretty good assumption.

If one assumes that nothing stops it, then the well of A gets deeper, and the well of B gets deeper, gradually over time. The speed at which each well gets deeper would depend on the amount of each mass.
I don't quite follow you here. If nothing stops what, exactly? Gravity is gravity; mass is mass. Why would the gravity change?
dnatwork
1.8 / 5 (5) Sep 15, 2017
[contd]
Notice the Hubble Constant isn't a constant any more. It varies over time; that's LDCM as opposed to the old Big Bang theory. It's not the only difference between them, but you're focusing on dark energy so I'm focusing on Lambda because that's dark energy.

That would seem to be true if relative motion is the only way to increase the space between objects. The speed of light is constant, so if i move away from the light source I get redshift. I'm postulating an additional way to increase the amount of space over time.
No. What this is, is a way to make it increase *faster* over time. That's what acceleration is. What you need the additional way for is to make it do it faster. That's what Lambda is: the acceleration factor. But the space expands the same way.


I think we said the same thing. The redshift should not increase in the absence of Lambda, but it does, so Lambda is needed to expand space. In LCDM.
dnatwork
1.8 / 5 (5) Sep 15, 2017
[contd]
Is there something in the theory that sets a limit, or is it assumed somewhere that X amount of mass will produce Y amount of curvature of spacetime, no more, no less?
Yes, precisely. And since we've never found anything that makes the part of gravity created by mass change, and since mass is conserved, we don't know of anything that will do that. So it's a pretty good assumption.

If one assumes that nothing stops it, then the well of A gets deeper, and the well of B gets deeper, gradually over time. The speed at which each well gets deeper would depend on the amount of each mass.
I don't quite follow you here. If nothing stops what, exactly? Gravity is gravity; mass is mass. Why would the gravity change?


Why would it not, is the question I started from. I'm saying you did find something that shows the part of gravity created by mass changing over time (accelerating expansion), but you've decided that is evidence of dark energy instead.
Benni
1 / 5 (8) Sep 15, 2017
the gravity well is the bowl created by the mass sitting in the middle of the rubber sheet. Light has to travel on the geodesics of that bowl


With a black hole, that bowl does down forever, or close enough, as light cannot get out. It is deeper than other gravity wells


The "bowl" in the middle of the rubber sheet defines the geodesics that a photon will travel, this is discussed in Einstein's General Relativity section "Photon Deflection". The Sun as a gravity well bends the path of a photon just passing it's peripheral disk by 1.75 arcseconds or 0.000486 degrees.

Equation of Deflection of light by the sun = 4GM/c²R, this is the exact equation Einstein used in GR & was subsequently measured to be accurate within 0.02% of accuracy, this is the curvature of deflected (gravitationally lensed) starlight, a simplified explanation of the formation of a gravity well if you please. From this has come all the complicated explanations of SPACETIME CURVATURE.

dnatwork
1.8 / 5 (5) Sep 15, 2017
You can see the effects of gravity wells (gravity itself, gravitational lensing, black holes, etc.). So you don't have to posit anything unsupported physics or circular arguments to say that gravity wells exist. The only thing you need to do with them is figure out how they behave in time and space. You don't have to defend their existence.

Dark energy is not that. The only reason for it is that it is needed to explain accelerating expansion within GRT. And the evidence for dark energy is...accelerating expansion. It's circular, and it serves no other purpose in the theory.

Occam's Razor says, cut that ugly thing off if you can find any other explanation.

You say, why would gravity change? I say, I don't know, but aren't you all trying to deal with the fact that it did, somehow or other? Isn't accelerating expansion exactly that?

Let gravity depend on both mass and time, see whether that leads to accelerating expansion, with everything else in GRT held the same.
Da Schneib
4 / 5 (4) Sep 15, 2017
I think we said the same thing. The redshift should not increase in the absence of Lambda, but it does, so Lambda is needed to expand space. In LCDM.
No, we didn't. Redshift increases with distance. It would even without Lambda. What it *doesn't* do without Lambda is increase at a *changing rate*.
dnatwork
1.8 / 5 (5) Sep 15, 2017
the gravity well is the bowl created by the mass sitting in the middle of the rubber sheet. Light has to travel on the geodesics of that bowl


The "bowl" in the middle of the rubber sheet defines the geodesics that a photon will travel, this is discussed in Einstein's General Relativity section "Photon Deflection"...

Equation of Deflection of light by the sun = 4GM/c²R, this is the exact equation Einstein used in GR & was subsequently measured to be accurate within 0.02% of accuracy, this is the curvature of deflected (gravitationally lensed) starlight, a simplified explanation of the formation of a gravity well if you please. From this has come all the complicated explanations of SPACETIME CURVATURE.



I'll take that as "You understood that part correctly."

So I guess I would change that equation to add a time factor, and that would create all kinds of havoc.
Hyperfuzzy
2.3 / 5 (3) Sep 15, 2017
Better idea, lets burn these papers.
Da Schneib
3.7 / 5 (3) Sep 15, 2017
@dnat, I don't understand what you mean by "drilling [a gravity well] deeper." X mass makes a gravity well Y deep. That's how deep it is and that's how deep it will stay, unless the mass or density changes. The mass, and the well, just sit there. Redshift doesn't change that, Lambda doesn't change that, Hubble Constant doesn't change that. The only things that change a gravity well is the mass getting bigger or smaller, or changing density.
Reg Mundy
2 / 5 (7) Sep 15, 2017
This thread is getting dangerously close to becoming almost sensible again, if we could just get rid of isatit. At least dgnatwick is putting forward a new idea, a rare burst of originality in amongst the usual dogmatic drivel. Mind you, I'm not saying he is right, but it bears consideration.
By the way, I won't mark him out of five as the whole rating system has long been discredited by sock-puppeteers who mark themselves up and anybody who disagrees with them down.
Da Schneib
3 / 5 (2) Sep 15, 2017
Also, if the gravity well changed over time, then *all* the light, not just that from far away, would show changing gravitational redshift (and BTW that's different than doppler, either due to the Hubble Constant or due to peculiar motion of the source). We wouldn't see that as a change in redshift for more distant objects; we'd see it as a change in redshift for *all* objects.

This is difficult, I know, @dnat, but you're making progress. Keep at it. You're still asking good questions.
Reg Mundy
1.8 / 5 (5) Sep 15, 2017
@Schnib
The only things that change a gravity well is the mass getting bigger or smaller, or changing density.

What's density got to do with it?
dnatwork
2.3 / 5 (6) Sep 15, 2017
I think we said the same thing. The redshift should not increase in the absence of Lambda, but it does, so Lambda is needed to expand space. In LCDM.
No, we didn't. Redshift increases with distance. It would even without Lambda. What it *doesn't* do without Lambda is increase at a *changing rate*.


I said it poorly, but that's what I was trying to say. I am taking redshift as change, do changing redshift is acceleration in my poor phrasing.
Da Schneib
3.7 / 5 (3) Sep 15, 2017
Why would it not, is the question I started from.
The question is not, "why would it not," but "why could it not." The answer is, if mass changed over time then we'd be able to tell because gravity would change over time for a given object, and we've never seen that (and we've looked). We make tables of where planets will be and they are checked by astronomers every day. If the masses of planets and the Sun changed over time, those tables would be inaccurate, and they're not. We've been doing this for hundreds of years, and for masses to change enough to do what you're talking about we'd be able to see it. And we don't. This is also true of galaxy clusters, and of double stars, and of globular clusters orbiting our galaxy and other nearby ones.

There really isn't anyplace to hide this sort of effect where we wouldn't see it. It cannot be true; the data say so. If a hypothesis does not match the data then it is incorrect.
Benni
1.4 / 5 (10) Sep 15, 2017
Redshift increases with distance. It would even without Lambda


Schneibo, you just totally blew it, Tired Light by Zany Zwicky.

Redshift does not increase with distance if there is no Lambda, that's the reason Lambda was invented, to come up with the physics for Doppler Effect Redshift.

Da Schneib
3 / 5 (4) Sep 15, 2017
I said it poorly, but that's what I was trying to say. I am taking redshift as change, do changing redshift is acceleration in my poor phrasing.
But changing redshift doesn't in and of itself indicate an accelerating rate of change of redshift. This is like confusing velocity and acceleration; acceleration is *rate of change of velocity*. They are not the same. In math terms, this is confusing the first derivative of distance with the second derivative, if you know the math to do derivatives.
Da Schneib
3.4 / 5 (5) Sep 15, 2017
Caper and lie all you like, @Lenni, this is a serious conversation so you are incapable of participating.

Unlike you @dnat is capable of changing opinions when presented with clear and compelling evidence. Not to mention polite.
dnatwork
2.3 / 5 (6) Sep 15, 2017
There really isn't anyplace to hide this sort of effect where we wouldn't see it. It cannot be true; the data say so. If a hypothesis does not match the data then it is incorrect.

I'm positing something so small you wouldn't see it in hundreds of years or within the local group.

But if you're right, you're stuck with dark energy. Other than the fact that it's the factor that's needed to make the equations fit the observations of accelerating expansion, is there any possible evidence for it?
Da Schneib
3.4 / 5 (5) Sep 15, 2017
And @dnat, note that @Lenni is giving you 1s because he's an azzhole. I have given you 5s because this is an interesting conversation.

In case you were wondering who the azzhole giving you 1s is. Ordinarily I might not give you 5s but azzholes like @Lenni must be opposed maximally. This does not always include bothering to respond to their azzhole posts, and I'm a lot more interested in you than @Lenni.
Da Schneib
3 / 5 (4) Sep 15, 2017
There really isn't anyplace to hide this sort of effect where we wouldn't see it. It cannot be true; the data say so. If a hypothesis does not match the data then it is incorrect.

I'm positing something so small you wouldn't see it in hundreds of years or within the local group.
It's not only the Local Group. It's other galaxy clusters within half a billion lightyears or so of here.

But if you're right, you're stuck with dark energy. Other than the fact that it's the factor that's needed to make the equations fit the observations of accelerating expansion, is there any possible evidence for it?
The evidence at hand is sufficient; but the explanation of it as Lambda is only a hypothesis, technically. It's currently only at 3 sigma, which may be sufficient for astronomers but is not for physicists. You shouldn't conclude that "dark energy" is some sort of thing. It's a placeholder for a thing we haven't fully figured out yet.
Da Schneib
2.3 / 5 (3) Sep 15, 2017
I queried Ethan Siegel regarding the interpretation that light is somehow "stretched by expanding space" and not due to motion (whether Hubble Flow or peculiar). I have not yet received a response and I expect none; Ethan is very conservative and probably doesn't understand the question I am asking. I still think that this whole "stretched by expanding space" thing is BS. I think it comes from not understanding frames of reference, or trying to avoid explaining them to "novices." Chickensxxt, quite frankly.

The right way to understand this is to comprehend that different frames see things in different ways. Not make up fairy stories about how "expanding space changes frequency." Pick a frame and stick to it. Energy is conserved in a frame; it is not conserved when shifting frames. This is obvious from SRT, you don't even need GRT for it.
Benni
1.4 / 5 (10) Sep 15, 2017
Caper and lie all you like, @Lenni, this is a serious conversation so you are incapable of participating.

Unlike you @dnat is capable of changing opinions when presented with clear and compelling evidence. Not to mention polite.


Schneibo, just get off the subject matter. All you are is a computer gadget geek trying to attain some self serving status as some kind of a scientist.

Anyone, and I mean ANYONE who would make so foolish a statement as
Redshift increases with distance. It would even without Lambda
is someone not worth another fraction of time for further reading.

Only one KNOWN thing causes redshift and Lambda does not fall into the realm of KNOWN.
Da Schneib
3.7 / 5 (6) Sep 15, 2017
Since @antialias appears to have reported @isatwit, I expect this next @Zeph clone to be gone shortly.

@Lenni, your MO is obvious to a three-year-old child. Why bother? You have already demonstrated that you cannot either do the math or understand the concepts; what do you think you have to contribute here besides fecal matter and rotting discards?
dnatwork
2.3 / 5 (6) Sep 15, 2017
Difficult to quote on phone. I'm still having the intuition that something about gravity is what's missing and it is not Lambda.

I think I read somewhere recently about statistical gravity. What if your chances of being affected by the gravity of an object depend on distance?

Flip a coin and if it's close by you are near 100%. You would never be able to see any effect at near distances or any human timescale.

But if it's really far away, the chances that you will miss become larger and larger. Flip the coin enough times and you will necessarily miss some percentage of the time. If you were moving in space at that moment, you would necessarily slip away from that distant object a little bit. Inertia. Add up all your percentages over billions of years and you will find yourself accelerating away from distant objects at a faster and faster rate.

Would this not derive the effects of lambda without having any unobservable energy out there to be called dark?
Da Schneib
3 / 5 (4) Sep 15, 2017
@dnat, I will point out that now you are retreating to more and more esoteric definitions of "gravity."

The facts are that we still don't know exactly what either dark energy or Lambda are; we know they are there because we can measure them.

I think you have overanalyzed what scientists think these things are; many people are making proposals to explain them. None has even really believable proof so far.
Hyperfuzzy
2.3 / 5 (3) Sep 15, 2017
@dnat, I will point out that now you are retreating to more and more esoteric definitions of "gravity."

The facts are that we still don't know exactly what either dark energy or Lambda are; we know they are there because we can measure them.

I think you have overanalyzed what scientists think these things are; many people are making proposals to explain them. None has even really believable proof so far.

https://drive.goo...=sharing
Benni
1.1 / 5 (10) Sep 15, 2017
@Lenni, your MO is obvious to a three-year-old child. Why bother? You have already demonstrated that you cannot either do the math or understand the concepts; what do you think you have to contribute here besides fecal matter and rotting discards?


Aw Schneibo, please do not accuse me of trying to be your clone.

I just love bouncing off the entertainment you provide to those of us who are serious about science but who also get a measure of enjoyment from the light hearted entertainment you so frequently provide with all your silly concepts of Black Hole Math & the like.

Hey, Schneibo, I'll ask it again.......Ever seen a Differential Equation you could solve?
Da Schneib
3 / 5 (4) Sep 15, 2017
@dnat, we have light, and light gives us information. It gives us spectra, and it gives us intensity, and it gives us presence of bright matter. From these three things we can tell much more than you might imagine.
dnatwork
2.3 / 5 (6) Sep 15, 2017
I have to wait to see this on a computer screen. I can't see quote levels and I can't tell who said what is chickenshit to whom.

I would say I'm not retreating to esoteric forms of gravity, I'm entertaining all of them at the same time.

Wouldn't reconciling GRT with quantum mechanics involve some statistical treatment of gravity anyway?
Da Schneib
2.3 / 5 (3) Sep 15, 2017
@dnat, reconciling GRT with QM requires quantum gravity, and we don't know much about quantum gravity. So far no one has a quantum gravity theory that makes predictions that are testable either mathematically or in the most powerful particle accelerators we have. I don't know what "some statistical treatment of gravity" means.
dnatwork
2.3 / 5 (6) Sep 15, 2017
I've passed the point of just being annoying. Signing off.
Benni
1 / 5 (7) Sep 15, 2017

Wouldn't reconciling GRT with quantum mechanics involve some statistical treatment of gravity anyway?
....here quoted directly from GRT:

Part III: Considerations on the Universe as a Whole- the structure of Space
Albert Einstein – General Relativity 1916

If we are to have in the universe an average density of matter which differs from zero, however small may be that difference, then the universe cannot be quasi-Euclidean. On the contrary, the results of calculation indicate that if matter be distributed uniformly, the universe would necessarily be spherical (or elliptical). Since in reality the detailed distribution of matter is not uniform, the real universe will deviate in individual parts from the spherical, i.e. the universe will be quasi-spherical. But it will be necessarily finite. In fact, the theory supplies us with a simple connection between the space-expanse of the universe and the average density of matter in it.

.....the 2nd Law of Thermodynamics

Hyperfuzzy
3 / 5 (2) Sep 15, 2017
or try
file:///C:/Users/Hyperfuzzy/OneDrive/Share/ModernPhysics.pdf
Da Schneib
4 / 5 (4) Sep 16, 2017
@dnat, in case there is some question, no, I didn't call you or your ideas chickensxxt. I was referring to a pet peeve of mine, about how the redshift due to expansion is, IMNVHO, mispresented to the lay public. Light doesn't get its frequency changed by moving through space. The idea is farcical. The very concept comes from not properly representing how frames of reference work, because they're "too complicated" for the "hoi polloi to understand." I have nothing but contempt for this. I think the "hoi polloi" should be respected, and I think it's chickenshxxt not to respect them in this.

When someone tries to lay this BS on you, you should immediately mark them as one of the arrogant pseudo-scientists, and tell them so in no uncertain terms. I hope to provide you with the ammunition to do so. But first you must understand frames of reference.
Reg Mundy
2.1 / 5 (7) Sep 16, 2017
@Schnib
The only things that change a gravity well is the mass getting bigger or smaller, or changing density.

What's density got to do with it?

Mmmm...it seems the only density relevant here is your density....
Benni
1.5 / 5 (8) Sep 16, 2017
@Schnib The only things that change a gravity well is the mass getting bigger or smaller, or changing density

What's density got to do with it?

Mmmm...it seems the only density relevant here is your density


OK, then you imagine you know so much about General Relativity along with Schneibo, let's see you produce the section of GR in which Einstein produced a new Fundamental Law of Physics that states an INFINITE WELL OF GRAVITY can exist above, at, or below the surface of a stellar mass called a black hole? Can you do it?

For years I've been challenging name calling neophytes like you & Schneibo to produce your Fundamental Laws of Physics that explains how INFINITE GRAVITY & INFINITE DENSITY can exist within the structure of a FINITE STELLAR BODY & this is the kind of slop & swill that comes back as an explanation:

what do you think you have to contribute here besides fecal matter and rotting discards?


artpletcher
Sep 16, 2017
This comment has been removed by a moderator.
dnatwork
1.8 / 5 (5) Sep 16, 2017
@dnat, in case there is some question, no, I didn't call you or your ideas chickensxxt. I was referring to a pet peeve of mine... The very concept comes from not properly representing how frames of reference work, because they're "too complicated" for the "hoi polloi to understand." I have nothing but contempt for this.
When someone tries to lay this BS on you, you should immediately mark them ... But first you must understand frames of reference.


I actually do understand, but I've been talking in the sloppy way it is generally presented.

A light source that is emitting blue light and moving away from you will appear shifted toward the red because every photon that is emitted will start from a position that is slightly farther away than the previous one. Not due to stretching of space, due only to the relative motion and the fact that light always travels the same speed through a given medium.
dnatwork
2.3 / 5 (6) Sep 16, 2017
But I also wasn't saying that the accelerating expansion might be due to stretching of space causing the light to stretch in transit. I was saying the effect of adding space in between two masses would be indistinguishable from relative motion. Therefore if you have relative motion causing a certain amount of redshift, but then you add more and more space on top of that relative motion, you would see an acceleration in the rate of apparent motion.

Dark energy says there is some new force being applied to push everything apart, faster and faster. My version says, no, that's just this obscure aspect of the gravity you already have in the system.
Da Schneib
3 / 5 (4) Sep 16, 2017
I actually do understand, but I've been talking in the sloppy way it is generally presented.
Frames are the only non-sloppy way to talk about this. It's been either tacitly or actively been part of physics since Galileo. The question has always been, "what frame are you measuring this in?" If it's not a consistent frame, then it quite simply is unphysical, because inconsistent frames mean energy is not conserved.

[contd]
Da Schneib
3 / 5 (4) Sep 16, 2017
[contd]
A light source that is emitting blue light and moving away from you will appear shifted toward the red because every photon that is emitted will start from a position that is slightly farther away than the previous one. Not due to stretching of space, due only to the relative motion and the fact that light always travels the same speed through a given medium.
This is incorrect. The frequency of a photon in a particular frame (in this case the observing frame) is determined by its source's motion in that frame. However, the frequency of a photon in the source frame is determined by atomic physics in that frame, so there is a record of the source frame as well.

It has nothing directly to do with "stretching space." In the observing frame, atomic physics in the source frame has always been slowed down by SRT. The photons were not altered by "stretching space." The observing frame was.
Da Schneib
3 / 5 (4) Sep 16, 2017
But I also wasn't saying that the accelerating expansion might be due to stretching of space causing the light to stretch in transit. I was saying the effect of adding space in between two masses would be indistinguishable from relative motion. Therefore if you have relative motion causing a certain amount of redshift, but then you add more and more space on top of that relative motion, you would see an acceleration in the rate of apparent motion.
But this is precisely "dark energy" or "Lambda." It's the third term on the left hand side of the EFE. The question is why.

Dark energy says there is some new force being applied to push everything apart, faster and faster. My version says, no, that's just this obscure aspect of the gravity you already have in the system.
But for this to increase there has to be an additional effect; otherwise everything would just keep on the way it is.
Benni
1 / 5 (10) Sep 16, 2017
In the observing frame, atomic physics in the source frame has always been slowed down by SRT


Schneibo, you don't even know what you meant with a gibberish statement like this, so with you trying to explain this kind of funny farm science gibberish, it's no wonder your just entertainment at it's.........
Hyperfuzzy
1 / 5 (2) Sep 16, 2017
I published this manuscript in 2015. (rejected by NRAC): tpbtheory dot com


even nobel is bs

they prized nothing they have a clue

tpbtheory? Dude, first logic, where is the unabigous truth, i.e. axiomatic first statement?
Try Charge exist and an E field relative to the center exist; charge is conserved; therefore, its field exist everywhere. The field only causes motion of other centers( else we'd be blind) ... Everything follows a set of rules defined by exach of these within an infinite space and an infinite set of pairs. Want me to define more details of common sense, theorectically? Each may occupy any point with another as long as the rules are satisfied. The rules tabulated by Maxwell!
Hyperfuzzy
1 / 5 (3) Sep 16, 2017
In the war of attraction and repulsion, attraction wins; however, the rest is controls!
Hyperfuzzy
1 / 5 (3) Sep 16, 2017
Pick a summation of each individual field upon each individual center of each body, i.e., use superposition, the other way is too complex even for your largest computer. After this see gravity, see atoms, crystals, supernovi, ... All the info is in the "emptiness" of space!
Benni
1 / 5 (9) Sep 16, 2017
But this is precisely "dark energy" or "Lambda." It's the third term on the left hand side of the EFE.


......and is precisely the reason Science Professionals such as myself have problems with your DE math & anything else dealing with DE, it totally violates the 2nd Law of Thermodynamics, but how would you know that Schneibo, you've never sat in a college classroom like I have studying Thermodynamics, taking a final exam & gotten a grade.

Schneibo, you don't even know what ENTROPY is, yet you pretend to know all there is to know about the EFE without ever having taken a courses in Nuclear Physics such as I have for which Thermodynamics is a pre-requisite.

The entire DE debate is an exercise in PERPETUAL MOTION because it is absent discussion of the fundamental law of thermodynamics of energy distribution, ENTROPY. Entropy is absent in the DE debate because DE requires an unbounded infinite environment which can't be had when inserting ENTROPY.

Hyperfuzzy
1 / 5 (3) Sep 16, 2017
Emptiness of space, an oxymoron!
Ojorf
3.9 / 5 (7) Sep 17, 2017
@Schnib
The only things that change a gravity well is the mass getting bigger or smaller, or changing density.

What's density got to do with it?

Mmmm...it seems the only density relevant here is your density....


Higher density steepens the gravity well.

Even small masses can theoretically be turned into black holes if compressed into a small enough space, i.e. high enough density.
Da Schneib
3 / 5 (2) Sep 17, 2017
@Ojorf, worth mentioning though that far from the center, the well is the same size no matter the density. It's only the slope inside that's affected by the density.
Benni
1 / 5 (8) Sep 17, 2017
Even small masses can theoretically be turned into black holes if compressed into a small enough space, i.e. high enough density.


ojorf,

No fundamental Law of Physics exists for this kind of ludicrous statement. Isawit makes more sense than you & Schneibo do.

According to BH theory, BHs form due to a well of gravitational attraction that becomes INFINITE at the surface of a stellar mass. It is an observed & measured Law of Physics that increased gravitational fields occurs ONLY by additional accumulation of MASS, not by increasing the DENSITY of a GIVEN MASS.

Keep it up, you're making Isawit look like a genius.
Benni
1.5 / 5 (8) Sep 17, 2017
Even small masses can theoretically be turned into black holes if compressed into a small enough space, i.e. high enough density.


ojorf,

No fundamental Law of Physics exists for this kind of ludicrous statement. Isawit makes more sense than you & Schneibo do.

According to BH theory, BHs form due to a well of gravitational attraction that becomes INFINITE at the surface of a stellar mass. It is an observed & measured Law of Physics that increased gravitational fields occurs ONLY by additional accumulation of MASS, not by increasing the DENSITY of a GIVEN MASS.

Keep it up, you're making Isawit look like a genius.


told you my iq is 97, why tease me in public?? i am a pig compared to you guys.


You're a genius compared to Ojorf & Schneibo, they think the hypotheses for the creation of Black Holes is a Fundamental Law of Physics, those two don't recognize Perpetual Motion even when it's slapping them silly up alongside of their heads.
Da Schneib
2.3 / 5 (3) Sep 17, 2017
Maybe the moderators will notice the decline of posts after they have allowed this spammer to post here. Maybe they won't. Having seen a lot of serious posters stop commenting here after the moderators failed to do anything I'd say it's a serious problem on physorg. But maybe that's just me.
dnatwork
1 / 5 (4) Sep 17, 2017
Even small masses can theoretically be turned into black holes if compressed into a small enough space, i.e. high enough density.

And how would that mass be compressed to such degree? Only by the addition of enough energy to the system to equal the amount of mass that it would normally take to create a black hole. According to e = mc2, that's a lot of energy. I believe that's why they theorize primordial black holes, because the last time there was that much energy available was at the Big Bang. Or am I completely wrong again?

If I'm right, then you're all saying correct things, but Benni is more correct because you could never create the situation where density is the point.
dnatwork
1.8 / 5 (5) Sep 17, 2017
Wouldn't reconciling GRT with quantum mechanics involve some statistical treatment of gravity anyway?
....here quoted directly from GRT:

Part III: Considerations on the Universe as a Whole- the structure of Space
Albert Einstein – General Relativity 1916

If we are to have in the universe an average density of matter which differs from zero, however small may be that difference, then the universe cannot be quasi-Euclidean... the theory supplies us with a simple connection between the space-expanse of the universe and the average density of matter in it.

.....the 2nd Law of Thermodynamics


@Benni, I don't get the connection. Unless you're saying the second law of thermodynamics says that gravity cannot slip in any situation, as that would be tantamount to creating energy from nothing?
dnatwork
1 / 5 (4) Sep 17, 2017
A light source that is emitting blue light and moving away from you will appear shifted toward the red because every photon that is emitted will start from a position that is slightly farther away than the previous one...
This is incorrect. The frequency of a photon in a particular frame (in this case the observing frame) is determined by its source's motion in that frame. However, the frequency of a photon in the source frame is determined by atomic physics in that frame, so there is a record of the source frame as well.


It is beginning to feel like no matter what I say, you will say I didn't understand. I know that within the frame where the photon is emitted, it is governed by that frame. But I was talking about redshift, which can only happen when observing from another frame. So when I said the second photon is emitted a little farther away than the first, that could only have meant from the perspective of an observer in some other frame.
dnatwork
1 / 5 (4) Sep 17, 2017
Also, the photon doesn't do any math. Talk all you like about transforms, but that is just math that is needed to make a model of what is actually happening. I'm trying to talk about the real world, not the math. Mostly because I don't know the math, but also because it is boring if it is not about the real world. If there is anything that is motivated solely by the need to have it in order to save the theory from itself, then it is time to "take it back to formula."
Da Schneib
3.7 / 5 (3) Sep 17, 2017
Even small masses can theoretically be turned into black holes if compressed into a small enough space, i.e. high enough density.
And how would that mass be compressed to such degree?
In the middle of a supernova.
Benni
1 / 5 (7) Sep 17, 2017
According to e = mc2, that's a lot of energy
The energy required to do it is INFINITE.

According to BH theoreticians, the reason a stellar mass becomes a BLACK HOLE is because the infinite force of gravity at the surface of a stellar mass is so intense that it can prevent a photon from reaching ESCAPE VELOCITY, thereby pulling the photon back to the surface so that we never see it.

The problem with the dumb theory is that an electro-magnetic wave ( photons) doesn't have an ESCAPE VELOCITY, this because as you say: E=mc².

Only particles of MASS rising from the surface of a stellar body have an ESCAPE VELOCITY, this because MASS is subject to the Law of Physics known as kinetic energy: KE= 1/2 mv². Remember in all this that a photon is not a particle.

Da Schneib
3.7 / 5 (3) Sep 17, 2017
I know that within the frame where the photon is emitted, it is governed by that frame. But I was talking about redshift, which can only happen when observing from another frame.
No, it aways was redshifted in that other frame. You're still not getting it.

Talk all you like about transforms, but that is just math that is needed to make a model of what is actually happening.
What is "actually happening" depends on what frame you measure it from.

Remember conservation of energy? Now, remember that it only applies in a single frame?

You're still not getting it.
dnatwork
1 / 5 (4) Sep 17, 2017
I'm objecting to dark energy because it smells like something for nothing. Conservation of energy says you should not have it come from nowhere. And it has gotten stronger over time, as the universe has expanded, but dark energy doesn't seem to have anything to say about that. and it can't interact with anything we can see, but it affects everything, etc.

I wanted to say that the accelerating expansion is just an emergent effect of what we already "know," not some new force that serves no other purpose. There's no conservation of space, but you could still say that has to have some cost, so my first idea ("there is no rubber sheet") is vulnerable to the same kind of criticism.

So I'm looking for another way of framing things that still captures the notions I started with.
Benni
1 / 5 (7) Sep 17, 2017
It is beginning to feel like no matter what I say, you will say I didn't understand


.....now you're beginning to catch on to the games being played. It never makes, which is the reason they "frame" their dialogue in the manner Schneibo is doing it, it's intended to make you feel as if you're profoundly stupid.
dnatwork
1 / 5 (4) Sep 17, 2017
Those notions were:

The presence of mass defines the curvature of spacetime, and the extent of space is defined by the time it takes light to travel from one mass to the next.

Light must follow the geodesic of curved spacetime.

The expansion of the universe seems to have been accelerating, and that acceleration has been increasing over time.

Concurrently with the acceleration, galactic groups have been getting denser relative to the rest of the universe.

But I was missing "the rest of the universe" before. That would be the intergalactic voids.

If space is defined by the presence of mass, must it not also be affected by the complete absence of mass?

If yes, what happens to the geodesics of spacetime around voids?

I posit that they balloon outwards, like the lines of a huge magnetic field. There is no added energy involved; on the contrary, that is simply the shape that space would have to take if you remove all energy from it.
dnatwork
1 / 5 (4) Sep 17, 2017
Cont'd.

Therefore, light could not travel across a void, but must go the long way round (must follow the geodesic). From our perspective, it appears to travel straight though, but "that is nonsense" because we are not there in the middle of the void to measure it. Light is known to go around high-mass objects and return to the "straight line" of its original trajectory (gravitational lensing). Why is it assumed to follow some other rule around a void?

In other words, if light is warped by extreme gravitational fields, shouldn't it be warped in the other direction by the extreme absence of gravity? Anti-gravitational lensing, that is.

Since the acceleration of expansion is coincident in time with the expansion of the voids, I think this has at least one advantage over dark energy. Two, if you count conservation of energy.
Da Schneib
3 / 5 (2) Sep 17, 2017
I'm objecting to dark energy
when it turns out that you always believed in it.

Sorry, I expected you to be capable of thinking. Apparently I was wrong.

I was nice. You're not. I'm turning and walking away.
dnatwork
1.7 / 5 (6) Sep 17, 2017
But I was talking about redshift, which can only happen when observing from another frame.

No, it aways was redshifted in that other frame. You're still not getting it.


It can't be redshifted in the other frame until it arrives in the other frame. If it were emitted in the other frame, it could not become redshifted in relation to that frame.

...that is just math that is needed to make a model of what is actually happening.

What is "actually happening" depends on what frame you measure it from.


You said frames aren't real things when I said they were. You can't have it both ways. Frames in standard theory are only measuring devices. Don't conflate the theory with the real world.
dnatwork
1 / 5 (4) Sep 17, 2017
Remember conservation of energy? Now, remember that it only applies in a single frame?

You're still not getting it.


I thought conservation of energy applied to the universe. You said frames aren't real things, so we can't reach into some other frame to get free energy. It was there or it wasn't; it doesn't matter if somebody measured it to make sure. I've heard about vacuum energy, etc., but that is precisely the kind of thinking that I'm objecting to.

No free lunch. Look instead for unseen but necessary consequences of the under-questioned assumptions of the theory.
dnatwork
1 / 5 (4) Sep 17, 2017
I'm objecting to dark energy

when it turns out that you always believed in it.

Sorry, I expected you to be capable of thinking. Apparently I was wrong.

I was nice. You're not. I'm turning and walking away.


Uh, what did I do that was not nice?

I never doubted that the observations of accelerated expansion need an explanation, nor have I doubted that GRT is the way to go. What I've been troubled by is the notion that the theory has been driven to the point that 70% of the universe must be invisible, have only this one effect, and it is labeled "energy" of any kind.

Yes, it's a placeholder name, to contrast with dark matter. But it's still some kind of energy they're looking for. Energy that wasn't there before, or that didn't have the same effect in an earlier epoch.

I'd prefer a way to avoid what seems fishy, and dark energy seems fishy.
dnatwork
1 / 5 (4) Sep 17, 2017
I can see how you guys get into fights.

I said "you said A and B, but B contradicts A. You can't have it both ways." That is not ad hominem, it is about the words and the validity of the argument. "You" is the general "you" and it is used in a common figure of speech.

Was I wrong about the words that were written (frames are real or not, redshift is between frames or always in its respective state in all frames)? I don't think so, but who can even tell with this thread anymore.

In response, I was told I'm not nice and not capable of thinking. That's ad hominem. Not about the words previously written, not an attempt to correct the record, but a personal insult.

Along the way I let slide all the times I was told I was not getting it, or whatever aspersions. I've had worse in other threads, but it's never necessary to be that way.
Benni
1 / 5 (8) Sep 17, 2017
No free lunch. Look instead for unseen but necessary consequences of the under-questioned assumptions of the theory.


Dark Energy theory is the most extreme form of "free lunch". The entire concept is that there is energy permeating the universe that will drive the motions of galaxies FOREVER. The problem being that there is only a limited amount of fuel from which to derive that ENERGY.

Stellar energy has only one source, transformation of MASS. Energy has only ONE KNOWN means of distribution, the 2nd Law of Thermodynamics, ENTROPY. When the means by which engines perform WORK is exhausted, the engine stops running because the fuel tank is empty & entropy has reached unity. This is precisely where DE hypotheses butts up against ENTROPY.

Entropy requires a system of closed boundaries or energy cannot distribute itself to be used for WORK, ie KINETIC ENERGY, that which gives motion to galaxies. DE denies a closed boundary system of energy distribution.
dnatwork
1 / 5 (4) Sep 17, 2017
I'm objecting to dark energy

when it turns out that you always believed in it.


Is this your way of saying that all the ideas I've put out there could all fall under the rubric of "dark energy" because it is only a placeholder, so I'm not even questioning the status quo?

If so, I would disagree. The way it is discussed is that "something" is pushing the universe apart, and there's more and more of this "something" over time. If that's just bullshit for the layman, well, I'm a layman, so I only get to eat bullshit in the first place.

I'm trying to think of ways that there is nothing added, not 70% on top but 0%. What could be missing in the understanding of the import of things that are already present or assumed in the theory? From the broadest possible conceptual standpoint because I'm the layman raised on a diet of nearly pure bullshit.
Benni
1 / 5 (8) Sep 17, 2017
I'm trying to think of ways that there is nothing added, not 70% on top but 0%. What could be missing in the understanding of the import of things that are already present or assumed in the theory?


The answer to your question is the 2nd Law of Thermodynamics, ENTROPY as I explained above. The universe has only a FINITE quantity of MASS that can be TRANSFORMED to energy, mass is not eternal therefore neither can energy be produced eternally, run out of fuel & you run out of the means to generate WORK to make galaxies move around the Universe.

There will come a day when all the stars in the Universe will have transformed all their mass to energy & simply blink out of existence because there is no fuel left to power the stellar engines. The only question remaining is what has happened to all the photons those stars produced in the past? They gotta still be floating around in outer space somewhere in accordance with the principles of Conservation of Energy.
dnatwork
1 / 5 (4) Sep 17, 2017
The answer to your question is the 2nd Law of Thermodynamics, ENTROPY as I explained above. The universe has only a FINITE quantity of MASS that can be TRANSFORMED to energy, mass is not eternal therefore neither can energy be produced eternally, run out of fuel & you run out of the means to generate WORK to make galaxies move around the Universe.

Entropy argues against dark energy being some actual new energy added to the system. It doesn't explain the accelerating expansion.

That is, I'm assuming they took into account the diminishing mass of the galaxies as the stars convert matter to energy that spins off into the void, thereby decreasing their gravity over time in a way that would look like something pushing them apart, and that would have a larger effect over time. They did, didn't they?
Hyperfuzzy
1 / 5 (1) Sep 18, 2017
Maybe there needs to be a logical review of entrophy. Since we measure energy by the relative wave's frequency and the number of active fields [ or massive body motion, ect. ]; then, what are you saying, entrophy always increases? I think that statement should be with many systems with variable number of states and degrees of freedom, (energy supply, type, size, infinite? Limited? Field Controlled?) the entrophy of the system will always increase? However, the scope of your law is not well defined nor the object measured. Any argument is moot!
dnatwork
1 / 5 (4) Sep 18, 2017
Even small masses can theoretically be turned into black holes if compressed into a small enough space, i.e. high enough density.

And how would that mass be compressed to such degree?

In the middle of a supernova.

A supernova only occurs with a star many times the mass of the sun. That is not a small amount of mass being compressed in isolation, which was the question.

Still no case offered where a small mass could reach sufficient density to become a black hole. Still true that density would do it, but still moot because it can't happen in the real world.
Benni
1 / 5 (6) Sep 18, 2017
Entropy argues against dark energy being some actual new energy added to the system. It doesn't explain the accelerating expansion.


Entropy fully explains the the distribution of energy everywhere. The best visual demonstration of ENTROPY is watching a fireworks display when those aerial bombs explode scatterring the visual effects in a spherical pattern until the heat that generates the color effects subsides due to lack of combustible fuel to keep the display going.

It doesn't explain the accelerating expansion.


Dark Energy is the target mechanism by which "eternal expansion" theory is postulated. Once again, if there is to be a process of "eternal expansion" there must be an eternal energy source to fuel the engine that makes those galaxies move.

Astrophysicists acknowledge from their limited knowledge of Nuclear Physics that the existence of MASS is a FINITE QUANTITY, what they won't acknowledge is that ONLY FINITE ENERGY can be derived from it.

Benni
1 / 5 (6) Sep 18, 2017
Maybe there needs to be a logical review of entrophy


Dark Energy theorists will never discuss ENTROPY with you. It's the reason Schneibo brushed off dnatwork in such a huff.

Most astrophysicists frame their arguments such that if you don't believe in the existence Dark Matter, Dark Energy, & Black Holes then you must be some kind of hayseed hick who never passed grade school science, then when you challenge them to explain how INFINITE ENERGY & INFINITE GRAVITY can be derived from a FINITE SOURCE of MASS, then the profanity name calling rants start, for example Schneibo.

then, what are you saying, entrophy always increases?
Yes, that is exactly what I'm saying. Entropy is calculable for any known system of energy. It's value lies between 0 & 1. When Entropy reaches the value of 1 (unity) energy distribution ceases because heat can no longer move beyond the boundary into which energy is being input, at this point WORK ceases.

dnatwork
1 / 5 (4) Sep 18, 2017

And how would that mass be compressed to such degree?

In the middle of a supernova.

A supernova only occurs with a star many times the mass of the sun. That is not a small amount of mass being compressed in isolation, which was the question.

I was hesitating to say this, but the only way I can make sense of the supernova comment is to construe it to mean you are positing a frame of reference that includes the center of a supermassive star while excluding the rest of the same star. Is that what you meant?

I may not have the math, but I can see that is not a valid frame of reference. Math lets you do anything. It is meaningless if it doesn't have a real world analogue. Drawing an arbitrary box between two atoms in the same gravitational field is a distinction without a difference.

If that's not what you were saying, please explain what distinction you were drawing.
dnatwork
1 / 5 (4) Sep 18, 2017
It doesn't explain the accelerating expansion.


Dark Energy is the target mechanism by which "eternal expansion" theory is postulated. Once again, if there is to be a process of "eternal expansion" there must be an eternal energy source to fuel the engine that makes those galaxies move.


You and I agree that dark energy doesn't hold water if it's supposed to mean infinite energy coming from nowhere. I'm saying the observations from accelerating expansion nevertheless need a mechanism to explain them. Do you agree?

If so, what could cause the universe to look like it's expanding faster and faster, without it actually being the case that something is pushing things apart more and more, entirely coincidentally with the age of the universe? That is, what is it about the age of the universe that creates this appearance, that isn't real but a quirk of our ability to observe and understand?

dnatwork
1.8 / 5 (5) Sep 18, 2017
Most astrophysicists frame their arguments such that if you don't believe in the existence Dark Matter, Dark Energy, & Black Holes then you must be some kind of hayseed hick who never passed grade school science, then when you challenge them to explain how INFINITE ENERGY & INFINITE GRAVITY can be derived from a FINITE SOURCE of MASS,


I don't question the existence of the phenomena being described; black holes are things whose effects can be observed so they need to be explained. I don't agree that means infinite gravity. That's actually a math error. Division by zero does not equal infinity, it is undefined. The axioms underlying the math simply don't tell you what to do with a zero divisor, which is kind of good because it's nonsensical in the real world.

So if the theory actually returns an infinite value, that's a blank spot in the theory, not a result. But if it's not infinite gravity, what is it, and how is it consistent with everything else?
dnatwork
1 / 5 (4) Sep 18, 2017
If so, what could cause the universe to look like it's expanding faster and faster, without it actually being the case that something is pushing things apart more and more, entirely coincidentally with the age of the universe? That is, what is it about the age of the universe that creates this appearance, that isn't real but a quirk of our ability to observe and understand?



Bad form to quote myself but I didn't finish my thought. So far I'm happiest with the idea that voids change the shape of spacetime the opposite way from concentrations of mass. Not by adding energy but by the exact same reason that mass curves spacetime. So you get a negative refraction around voids, and light takes longer to go around them. That causes more and more redshift as the voids get bigger, without anything actually moving relative to anything else.

If Friedmann said space is flat, maybe I'm saying it has negative flatness in some places?
TimLong2001
1 / 5 (1) Sep 18, 2017
The apparent acceleration of the "Big Bang expansion" is, rather, an indication that the rate that photons lose energy from their internal dynamical process as they travel across the universe is greater than a velocity corresponding to a constant or decelerating velocity calculated by interpreting the red shift as a Doppler shift.
Benni
1 / 5 (5) Sep 18, 2017
I'm saying the observations from accelerating expansion nevertheless need a mechanism to explain them. Do you agree?


I agree, but there is another problem here, "accelerating expansion". Sez who? Someone who imagines they've properly analyzed an infrared spectroscopy slide? If we are to believe in an accelerating expansion theory that some now claims approaches the speed of light, then why hasn't the entire Universe already disappeared from sight except for local galaxies? Once again the answer is what they won't talk about, ENTROPY.

Nothing moves without an input of energy. Many astrophysicists claim to have evidence that distant galaxies are moving at a velocity approaching speed of light, this beggars the question, why are local cluster galaxies not doing this? Now enter the explanation, Dark Energy, that DE is what provides the energy source to move distant galaxies velocities approaching light but they can't explain why DE does not exist LOCALLY.

dnatwork
1 / 5 (4) Sep 18, 2017
I'm saying the observations from accelerating expansion nevertheless need a mechanism to explain them. Do you agree?


I agree, but there is another problem here, "accelerating expansion". Sez who? Someone who imagines they've properly analyzed an infrared spectroscopy slide? If we are to believe in an accelerating expansion theory that some now claims approaches the speed of light, then why hasn't the entire Universe already disappeared from sight except for local galaxies? Once again the answer is what they won't talk about, ENTROPY.


I'm still not getting how entropy by itself is the explanation for this thing that looks like accelerated expansion. I get how entropy and conservation of energy should rule out the idea that the thing they call dark energy is actually new energy added to the system. But something more is needed to explain the appearance of additional redshift over time. All entropy does is stop the system at equilibrium.
dnatwork
1 / 5 (4) Sep 18, 2017
Nothing moves without an input of energy. Many astrophysicists claim to have evidence that distant galaxies are moving at a velocity approaching speed of light, this beggars the question, why are local cluster galaxies not doing this? Now enter the explanation, Dark Energy, that DE is what provides the energy source to move distant galaxies velocities approaching light but they can't explain why DE does not exist LOCALLY.


Agreed. But if we agree that "dark energy is added energy, but only far away and only at certain times" is logically inconsistent with everything else (specifically, that all laws apply the same way everywhere, and every difference you see is because of changing frames of reference), then we can move on to what mechanism might actually produce the observed phenomena, that happen to look like accelerating expansion at first glance.
Benni
1 / 5 (6) Sep 18, 2017
black holes are things whose effects can be observed


What "effects"?

I don't agree that means infinite gravity.
......but the underlying supposition of BH theory is that infinite gravity exists at a BH surface preventing photons from reaching ESCAPE VELOCITY, such a theory subjects electro-magnetic energy to the Laws of Kinetic Energy physics which governs speeds of particles of MASS with regard to acceleration.

Electro-magnetic waves do not accelerate or decelerate based upon adding or subtracting some quantity of energy input to speed them up or slow them down, yet this is what BH Enthusiasts imagine what can happen if an EM Wave gets caught up in a sufficiently strong gravity field, that the force of a gravitating body can slow down a photon.

The only thing that can happen to a photon that can change it's existence is TRANSFORMATION back to MASS & that is not a process by which it's speed can be magically changed as BH Theory postulates.

dnatwork
1 / 5 (4) Sep 18, 2017
So Hubble found the redshift, and then they figured out that was caused by relative motion, and now all redshift is due to relative motion. There's a logical fallacy in there. If some redshift is due to relative motion, that does not mean all redshift is due to relative motion.

The comment was made above that "we've looked for such effects, and they can't be found." What if they can't be found because people didn't look at things they thought they had already explained? What if all redshift is only partly due to relative motion, and another component is the sort of thing I've been saying? So if you actually sat still relative to some other system for a billion years, you would have a little redshift; but when you saw that redshift, you'd mistakenly conclude you were moving just a little bit.

Then the effects I've been positing would actually be occurring everywhere all the time (answering that criticism), but the theory would be missing their contribution to the results.
dnatwork
1 / 5 (4) Sep 18, 2017
black holes are things whose effects can be observed


What "effects"?


Orbits of stars near galactic centers?

I have to split this in two due to number of characters in quoted text.
Benni
1 / 5 (6) Sep 18, 2017
But something more is needed to explain the appearance of additional redshift over time. All entropy does is stop the system at equilibrium.
...........it's the BOUNDARY that causes energy distribution (entropy) for the creation of WORK, it must be CLOSED, no leaks or the system shuts completely down soon after it starts, everything will go out in a big fizzle.

But something more is needed to explain the appearance of additional redshift
.....misinterpretation of the spectroscopic data. It goes back to begging the question as to why local galaxies do not move at speeds approaching that of light. So if local galaxies do not do this, what is the stroke of celestial magic that enables ONLY distant galaxies to accelerate beyond the the known velocities peculiar to local galaxies.

The energy input to make even the smallest particle mass move at Relativistic Velocities is incredible, but imagine trying to do that with an entire galaxy? Or millions? Calculate that.

dnatwork
1 / 5 (4) Sep 18, 2017
I don't agree that means infinite gravity.

......but the underlying supposition of BH theory is that infinite gravity exists at a BH surface preventing photons from reaching ESCAPE VELOCITY, such a theory subjects electro-magnetic energy to the Laws of Kinetic Energy physics which governs speeds of particles of MASS with regard to acceleration.

Electro-magnetic waves do not accelerate or decelerate based upon adding or subtracting some quantity of energy input ... BH Enthusiasts imagine what can happen if an EM Wave gets caught up in a sufficiently strong gravity field, that the force of a gravitating body can slow down a photon.

Yeah, that sounds like nonsense, but I said I don't know the math. I thought the reason light couldn't get out was because space is contracting faster than light can pass through it. Every photon is still going 300,000 km/s, but 300,000.1 km of space is being added in front of it every second, so to us it appears to stand still.
dnatwork
1 / 5 (4) Sep 18, 2017
But something more is needed to explain the appearance of additional redshift

.....misinterpretation of the spectroscopic data.


Yes, that's what I've been saying. They seem to be assuming there is a zero lower bound for the curvature of spacetime, therefore any additional redshift must be due to additional motion. But if there is no lower bound (there is no rubber sheet, or the flatness of spacetime can be negative, or both plus more oddities), then the data can be interpreted differently.

...but imagine trying to do that with an entire galaxy? Or millions? Calculate that.


Luckily, I don't need to because I'm saying there's something wrong with the assumption that relative motion is the driver behind all that redshift.

The light had to follow a longer path to get here, and the length of the path increased between the emission of one photon and the next. The answer is to be found in the path, not just the objects at either end.
Benni
1 / 5 (6) Sep 18, 2017
So Hubble found the redshift, and then they figured out that was caused by relative motion, and now all redshift is due to relative motion


Redshift he discovered was a LOCAL galaxy, not something 10 Gyrs distance.

There's a logical fallacy in there. If some redshift is due to relative motion, that does not mean all redshift is due to relative motion.
....almost.

Interstellar space is not a big empty void. Within every cubic kilometer of space interplanetary satellites detect about a dozen micron sized particles, call it dust if you wish, but this is data collected by hit counters from actual hits on satellites.

When an photon hits a particle it can undergo INELASTIC SCATTERING. Compton scattering is the inelastic scattering of a photon by a charged particle, usually an electron. It results in a decrease in energy (increase in wavelength) of the photon, hence a redshift effect due to the statistical probability over distance of such a collision.

Benni
1 / 5 (6) Sep 18, 2017
The light had to follow a longer path to get here, and the length of the path increased between the emission of one photon and the next. The answer is to be found in the path, not just the objects at either end.
......the Shapiro Effect, that there can be an APPARENT change of photon velocity, whether observing the photon dead on or at a parallax view from the source, the photon's velocity has actually has not changed, the change is simply an apparent change & not a real change causing a measurable time delay.
Benni
1 / 5 (6) Sep 18, 2017
Should have added a couple of words to my last sentence from my last post

the change is simply an apparent change & not a real change causing a measurable time delay.
........ changed to include the addition of the capital lettered words as noted below:

........ the change is simply an apparent change & not a real change BUT ONE causing a measurable time delay.
Da Schneib
3 / 5 (2) Sep 18, 2017
@dnat, let me be completely clear: If I see willingness to learn, I'm there. If not, not. Just as simple as that. You keep ignoring what I've posted and re-asserting your initial thesis. This is not promising and I've dealt with a lot of individuals who show this pattern of behavior and wind up being trolls. I have no time for trolls.

I'm not posting my opinion; I'm posting what physics theories say about how things work. If you don't like it you'll need to address the physicists say and you'll need to do it in a peer reviewed format. If you can't do that, then you're just another conspiracy theorist.

Noting how you behave is not ad hominem. It's fact. Get over it.
Benni
1 / 5 (6) Sep 18, 2017
I'm posting what physics theories say about how things work
......for sure you're doing this, posting theories, but that is all PERPETUAL MOTION is and has never stood the test of standing in for the Fundamental Laws of Physics.......believing a finite stellar mass can have infinite density caused by an infinite gravity field has never been a Fundamental Law of Physics, but you sure do think so......and you would have me labeled as a troll if you were a moderator here.

dnatwork
1.8 / 5 (5) Sep 18, 2017
@dnat, let me be completely clear: If I see willingness to learn, I'm there. If not, not. Just as simple as that. You keep ignoring what I've posted and re-asserting your initial thesis.


You never addressed the problems with apparent energy from nothing, you keep asserting that that is what the theory states. Yes, it does, and it then requires energy from nothing, so it's circular.

And I think you have reference frames wrong if you think it is valid to say the center of a supernova is a small mass, which you did to prove your point about density in the absence of large masses.

This is not promising and I've dealt with a lot of individuals who show this pattern of behavior and wind up being trolls. I have no time for trolls.


You turned away when I pointed out logical inconsistencies in what you said.
Da Schneib
3.7 / 5 (3) Sep 18, 2017
@dnat, this is why I don't bother with people who don't listen.

There isn't any energy from nothing. The longer you post the more you sound like one of the EUlunaitics.

Your perceived "logical inconsistencies" are due to your lack of understanding of what frames of reference mean, and you won't listen to any correction.

This is useless. If you want to learn something new, I'm here. If you're armored up I have no time for trolls.
dnatwork
1.8 / 5 (5) Sep 18, 2017
I'm not posting my opinion; I'm posting what physics theories say about how things work. If you don't like it you'll need to address the physicists say and you'll need to do it in a peer reviewed format. If you can't do that, then you're just another conspiracy theorist.

Noting how you behave is not ad hominem. It's fact. Get over it.


Not nice, can't think, now conspiracy theorist--those are ad hominem. "Get over it" is antagonistic phrasing. Be honest about losing your temper.

If I were in a position to publish in a peer-reviewed journal, I would never visit this site. That's simply a nonsensical rebuke, the same kind I've seen before from frustrated posters. And if it's true for me, it's doubly true for you.

The fact is, the best physicists in the world don't really know what gravity is, let alone dark energy. They have math models, theories. They admit it.

Your comments have helped me understand the holes in my thinking. Have you looked for any in yours?
dnatwork
1 / 5 (4) Sep 18, 2017
@dnat, this is why I don't bother with people who don't listen.

There isn't any energy from nothing. The longer you post the more you sound like one of the EUlunaitics.


I've been waiting to hear what is pushing the universe apart. Did you say it was inflation? What is that, if not some form of energy?

Your perceived "logical inconsistencies" are due to your lack of understanding of what frames of reference mean, and you won't listen to any correction.


I'm listening, but your point is not clear. I said redshift is due to the source of the light moving away from us; you said no, it was always redshifted in our frame. That is the opposite of everything I've heard about it.

If "it was always redshifted," as you wrote, then it had to be in our frame always, including at the time it was emitted. That would mean it was emitted as red for us, but as blue for the folks in the other frame. That violates the universal application of the laws of physics.
dnatwork
1 / 5 (4) Sep 18, 2017
If that's not what you meant, then you were the one with the sloppy language.

Did you mean "It was always going to be perceived as redshifted in our frame, because our frame is moving relative to the source of emission, but I don't mean to imply that the same emission results in redder light in our frame"?

If yes, please explain how that is different from what I said, that the redshift occurs because the source is moving away from us. It's emitted as blue in both places, but our relative motion makes it appear red.
dnatwork
1 / 5 (4) Sep 18, 2017
Also, how does the center of a supernova count as a small mass with great density? Was that about reference frames or not? Do you think it is valid to define a reference frame in that way, in an argument about density versus mass being the source of gravity?

I asked, said I don't think it's valid, and you turned away. You didn't respond and correct the impression you gave with the words you wrote.

You could have said oh, wait, that was a brainfart, never mind. Or you could have defended it. But you went straight to "you obviously can't think, I'm so disappointed that you're a troll."

Like I said, be honest about your reactions (and any mistakes--this is not peer-reviewed, as you said) and everybody's okay. This is just some site with press releases, and none of us are qualified to write the papers in question.

Refuse to engage with questions about what you said, call people names when they disagree, and it reflects on you.
Da Schneib
3.7 / 5 (3) Sep 18, 2017
Sorry, man, it's about how you behave. If you don't like being classified that way don't behave that way. Trolls aren't trolls because they're trolls; they're trolls because they behave like trolls.

It's not what you are (ad hominem); it's how you behave.
RealityCheck
1.5 / 5 (8) Sep 18, 2017
@Da Schneib.
@dnatwork...
If you want to learn something new, I'm here. If you're armored up I have no time for trolls.
The greatest crime against Science and the Scientific method/discussion principles is to MISTEACH based on OLD and Falsified paradigms which have NEVER HAD any tenable objective scientific support (as Prof. Roger Penrose and Prof. Paul Steinhardt have recently admitted was the case for Big Bang and Inflation/Expansion etc hypotheses/interpretations maths/models of observations).

That you accuse @dnatwork of not wanting to learn something new and/or being a troll, must be the most hypocritical, irony-laden, egotistically driven comment you have ever made, mate! How can you not see YOU'RE 'parroting' trolling/spamming/insulting because he disagree with YOU because it's YOU FAILING to "learn something new", DS?

There was/is NO Big Bang, Inflation, Expansion; it's OLD naive/MIS-interpretations of observations.

LEARN, DS. STOP 'parroting' OLD CRAP, OK?
dnatwork
1 / 5 (4) Sep 18, 2017
Way to difficult to quote on this phone, but for the record I'm not questioning the Big Bang or a bunch of other things. I'm challenging the interpretation of apparent acceleration in the apparent expansion of the universe as necessarily leading to dark energy, if that is supposed some actual form of energy pushing things apart. And when I start from that question, and the answer seems to be that dark energy is necessary because of the apparent acceleration, I have to challenge that as apparently circular reasoning.

"Can't there be some other explanation of this observation?"

"No there can't because the observation is explained this way in the theory."

It comes across as absurd.
dnatwork
1 / 5 (4) Sep 18, 2017
Still not seeing any response to direct questions about what was meant by the middle of a supermova and light always being redshifted, but I do see another comment calling me a troll. If there's time to do that, there's time to address the questions above.

Whenever someone has the option to do something but they don't, then they chose not to. If they do something else, they chose that, too. What choices were made here today, and by whom?

Me, I'm a guy with a logical brain but not much math who reads press releases about physics. I had to put my cat down this weekend. I'm just here because it's better to do something interesting even if I'm not good at it. And I've been honest about that from the start.

I can't actually follow half of the leads that da Schneib points to, and he should not expect that I could, but he gets mad because I don't get it, he says. I do get when someone's words are inconsistent, though.

But I'm the troll, I guess.
Da Schneib
5 / 5 (2) Sep 18, 2017
@dnat, the acceleration is real. So is expansion. If you have a better explanation then bring it. So far all I've seen is avoidance of anything that challenges your statements, and misunderstanding of both the EFE and frames of reference.

"Dark energy" is right there in the EFE and its interpretation supports everything astrophysicists and cosmologists say about it. If you think not, nothing you've said so far supports that position; in fact, the best thinking you've done actually turns out to be exactly what those same astrophysicists and cosmologists say.

If you think there's some other explanation bring it; so far you're just agreeing with them and denying it because you don't understand frames of reference. It's a shame that you don't understand why frames of reference lead you to incorrectly conclude it's circular reasoning, but that doesn't mean everyone else is wrong.
dnatwork
1 / 5 (4) Sep 18, 2017
What is EFE?

How does middle of a supernova prove point about density and black holes?

How is it valid to say the light was always redshifted in the second frame?

If I'm necessarily wrong, what's up with these guys publishing articles where they question the theiory of dark energy? They are also wrong a priori? Or are all of these theories, and none of them proven ?
RealityCheck
1.5 / 5 (8) Sep 18, 2017
@dnatwork.
Way to difficult to quote on this phone, but for the record I'm not questioning the Big Bang or a bunch of other things. I'm challenging the interpretation of apparent acceleration in the apparent expansion of the universe as necessarily leading to dark energy, if that is supposed some actual form of energy pushing things apart. And when I start from that question, and the answer seems to be that dark energy is necessary because of the apparent acceleration, I have to challenge that as apparently circular reasoning.
That is a sensible approach to science discourse, mate; keep it up in all your discussions. :)

However, your/DS's foregoing discussion/points are NOW MOOT; no longer seriously held by mainstream science NOW DISCOVERING NEW things; and bravely REVIEWING ALL Big-Bang-related claims objectively.

Since there was/is NO Big Bang OR Inflation OR Expansion/Accelerated Expansion, it is futile to argue claims/explanations which have NO MEANING.

OK? :)

Da Schneib
3.7 / 5 (3) Sep 18, 2017
Einsten Field Equations. It's the mathematical statement of GRT.

Supernovae make powerful enough explosions that they can compress matter to a high enough density to form black holes.

Light doesn't change frequency in a consistent frame.

I never said they were wrong. I'm not sure they are. But they aren't saying what you're saying.
Benni
1 / 5 (6) Sep 18, 2017
@gnatwork,

"On Stationary Systems with Spherical Symmetry consisting of many Gravitating Masses"

Albert Einstein- Oct 1939

The Conclusion at the end is poignant, with the essential result of this investigation being a clear understanding as to why the "Schwarzschild singularities" do not exist in physical reality. The "Schwarzschild singularity" does not appear for the reason that matter cannot be concentrated arbitrarily, this is due to the fact that otherwise the constituting particles would reach the velocity of light. The entire paper can be read here:

http://www.cscamm...hild.pdf

After 23 years since publishing GR, Einstein finally got fed up with astro-physicists trying to apply Einstein's Photon Deflection section of GR as the basis for an argument that BHs can exist via Schwarzschild funny farm math, that is math that models density dependent gravity versus mass dependent gravity.
dnatwork
1 / 5 (4) Sep 18, 2017
I have brought ideas but they've been rejected out of hand.

Einstein came out with GRT decades before Hubble discovered red shift. According to the formulas in GRT, relative motion would cause red shift, so they settled on that as the explanation. Yay.

But what GRT actually says his wife always goes the same speed no matter your frame of reference. Thermodynamics says energy is conserved. But nothing says that space is conserved. On the contrary, GRT says that spacetime is defined and shaped by the presence of mass.

Therefore, one idea I have put forward is that space is shaped differently in different places, an additional mechanism that forces light to follow a longer path. Another was that gravity wells increase over time, slowly.

Those ideas are not the same as any theory that says things are being pushed apart, but they are consistent with the notion of black holes being places where space is contracting faster than light can get out.

I tried, right or wrong.
RealityCheck
1 / 5 (7) Sep 18, 2017
@Da Schneib.
Einsten Field Equations. It's the mathematical statement of GRT.
DS, that's a descriptive/predictive abstract geometric maths-model theory not completely reflecting, let alone actually explaining, the actual real entities/processes involved behind what we observe/describe/model ABSTRACTLY.
Supernovae make powerful enough explosions that they can compress matter to a high enough density to form black holes.
DS, it takes a CUMULATIVE 'critical mass' of mass-energy, just density is not enough; since LESSER THAN a MINIMUM 'critical mass-energy' CUMULATIVE quantity CANNOT GENERATE SUFFICIENT gravity CONTAINMENT force/effect against QUANTUM MECHANICAL forces/processes involved. Hence why there exist NO MICRO BLACK HOLES ('primordial' or not).

I already had this out with rpenner and another poster in the old physorg/physforum. I explained why LHC and observed space contains NO 'Micro' black holes.

So your insistence on DENSITY per se is WRONG, DS.

OK?
Benni
1 / 5 (6) Sep 18, 2017
one idea I have put forward is space is shaped differently in different places
.....below quoted directly from GR:

Part III: Considerations on the Universe as a Whole- the structure of Space
Albert Einstein – General Relativity 1916

"If we are to have in the universe an average density of matter which differs from zero, however small may be that difference, then the universe cannot be quasi-Euclidean. On the contrary, the results of calculation indicate that if matter be distributed uniformly, the universe would necessarily be spherical (or elliptical). Since in reality the detailed distribution of matter is not uniform, the real universe will deviate in individual parts from the spherical, i.e. the universe will be quasi-spherical. But it will be necessarily finite. In fact, the theory supplies us with a simple connection between the space-expanse of the universe and the average density of matter in it."

Benni
1 / 5 (7) Sep 18, 2017
Einsten Field Equations. It's the mathematical statement of GRT.
What ? That Einstein GR can be twisted to suggest GR can provide a basis for Schwarzschild's BH Math.

Supernovae make powerful enough explosions that they can compress matter to a high enough density to form black holes.
You need to set aside some time & read:

"On Stationary Systems with Spherical Symmetry consisting of many Gravitating Masses" in which Einstein refutes everything you just stated.

Albert Einstein- Oct 1939

http://www.cscamm...hild.pdf

Facts can be bothersome, right Schneibo?
Uncle Ira
4.3 / 5 (6) Sep 18, 2017
@ Bennie-Skippy. How you are Cher? I am fine and dandy, thanks for asking.

Part III: Considerations on the Universe as a Whole- the structure of Space
Albert Einstein – General Relativity 1916
Skippy, you are a one trick pony Cher. How many times you post that same snip & glue? Did Einstein-Skippy also tell you that he thought that before anybody had humongous telescopes, and before anybody had proof of other galaxies, and before the other Skippys cyphered out the three solutions to the General Theory (that he could not do yet)? Flat,,, Curve in,,,, & Curve out.

He wrote a lot of stuff after 1916, one of the things he wrote is "Observation trumps theory every time". Who you are going to believe? Einstein-Skippy who was not the observer, or all the peoples who came after him and see the space expanding and see the universe is so flat they can not observe any curvature.

You seem to think that physics was over in 1916.
Uncle Ira
4.3 / 5 (6) Sep 18, 2017
P.S. for you Bennie-Skippy.

In 1916 Einstein-Skippy still had not completed a solution to his field equations. He had to wait on Schwarzschild-Skippy and De Sitter-Skippy and Friedman-Skippy to do the complete solutions.
Whydening Gyre
5 / 5 (5) Sep 18, 2017
...but the underlying supposition of BH theory is that infinite gravity exists at a BH

Actually... the "math" says the center (I say just - maximum...)The surface - just enough to change the angular trajectory of a photon.
Electro-magnetic waves do not accelerate or decelerate based upon adding or subtracting some quantity of energy input ...

Correct. Speed of light.
BH Enthusiasts imagine what can happen if an EM Wave gets caught up in a sufficiently strong gravity field, that the force of a gravitating body can slow down a photon.

See above. Angular trajectory. Not speed.
I thought the reason light couldn't get out was because space is contracting ... so to us it appears to stand still.

Fanciful, but incorrect. If a photon is constantly changing it's direction, that energy/speed must transfer somewhere else. My own supposition is - spin. Benni might call it transformation to mass...
Benni
1 / 5 (6) Sep 18, 2017
My own supposition is - spin. Benni might call it transformation to mass.


No, that is just another one of your "suppositions", spin angular momentum has nothing to do with TRANSFORMATION.
Hyperfuzzy
1 / 5 (1) Sep 18, 2017
Enough! Modern Physics is a sham! So ...
Benni
1 / 5 (7) Sep 18, 2017
He wrote a lot of stuff after 1916,


Yep, including this: "On Stationary Systems with Spherical Symmetry consisting of many Gravitating Masses"

Albert Einstein- Oct 1939

"The Conclusion at the end is poignant, with the essential result of this investigation being a clear understanding as to why the "Schwarzschild singularities" do not exist in physical reality. The "Schwarzschild singularity" does not appear for the reason that matter cannot be concentrated arbitrarily, this is due to the fact that otherwise the constituting particles would reach the velocity of light. "

The entire paper can be read here:

http://www.cscamm...hild.pdf

Maybe you have another Einstein Paper with a post 1916 date? This one is 1939.
Benni
1 / 5 (7) Sep 18, 2017
P.S. for you Bennie-Skippy.

In 1916 Einstein-Skippy still had not completed a solution to his field equations. He had to wait on Schwarzschild-Skippy and De Sitter-Skippy and Friedman-Skippy to do the complete solutions.


......and completely debunked it in 1939 with: "On Stationary Systems with Spherical Symmetry consisting of many Gravitating Masses". He totally trashed Schwarzschild's BH Math

Now coming to your math, it is so miserable that you cannot add or subtract spans of time between dates. I even did it for you above, 23 years but it never registered. I can see why you give Schneibo 5 Star votes, both of you have the same math problem.

Uncle Ira
4.3 / 5 (6) Sep 18, 2017
If there is a singularity or not is a different question from whether there is a black hole or not. Nice try though.

Even Schwarzschild-Skippy would have told that the "singularity" is nothing more than the place where the maths don't work anymore. It is just a word for "we can not go any further until we discover something new".

All the maths, physics, and observations agree. (The only people who don't agree are the crankpots and such like.) There are black holes. What is happening to the matter in there is still being pondered.
Whydening Gyre
5 / 5 (6) Sep 18, 2017
Einstein's Photon Deflection section of GR as the basis for an argument that BHs can exist via Schwarzschild funny farm math, that is math that models density dependent gravity versus mass dependent gravity.

Again, Benni...
When is gravity NOT dependent on the density of mass? A molecular sized mass still has a little gravity. More mass = more gravity. (Which, incidentally, when sufficient enough, will cause compaction)
Density is a physical descriptor of a mass(ive) structures internal component masses.
So, if gravity (the total collection of mass) is sufficient to compact it's structure, that means it's volume will eventually decrease. (ergo, increased density). Hence, a larger portion of the total gravity is felt at any discrete surface locale.
Use your inverse square law to figure it out...

Benni
1 / 5 (7) Sep 18, 2017
All the maths, physics, and observations agree. (The only people who don't agree are the crankpots and such like.) There are black holes. What is happening to the matter in there is still being pondered.


Well how about that, your own words
The only people who don't agree are the crankpots and such like
explain your inability to do a simple math dating problem & come up with 23 years, back to Ignore.
Benni
1 / 5 (7) Sep 18, 2017
Again, Benni...
When is gravity NOT dependent on the density of mass?
...... it's another one of your suppositions, prove it.
Whydening Gyre
5 / 5 (4) Sep 18, 2017
My own supposition is - spin. Benni might call it transformation to mass.


No, that is just another one of your "suppositions", spin angular momentum has nothing to do with TRANSFORMATION.

Sufficient gravity can quite possibly transfer forward momentum into spin momentum.
How many photon revolutions per second would translate into the speed of light per second?
Quite a few, I'm guessin'...
And that might appear to be "dense" enough to look like - mass...
Whydening Gyre
5 / 5 (5) Sep 18, 2017
Again, Benni...
When is gravity NOT dependent on the density of mass?
...... it's another one of your suppositions, prove it.

Take a 2 inch diameter ball of styrofoam. Drop it on your foot.
Take a 2 inch ball of lead. Drop it on your foot.
You need a further example?
Benni
1 / 5 (6) Sep 18, 2017
My own supposition is - spin. Benni might call it transformation to mass.


No, that is just another one of your "suppositions", spin angular momentum has nothing to do with TRANSFORMATION.

Sufficient gravity can quite possibly transfer forward momentum into spin momentum.
How many photon revolutions per second would translate into the speed of light per second?
Quite a few, I'm guessin'...
And that might appear to be "dense" enough to look like - mass...


Exactly the same mistake Schneibo makes, trying to subject an electro-magnetic wave to the Law of Physics of kinetic energy, treating an EM wave as if it were a particle of mass.
dnatwork
1 / 5 (4) Sep 18, 2017
I'm glad you guys are fighting and nobody picked up on my typo about Einstein's wife always going the same speed. I guess she was the light of his life?
Da Schneib
5 / 5 (2) Sep 18, 2017
I have brought ideas but they've been rejected out of hand.
No, evidence has been presented that they were wrong, and not all of them- your deepest idea turned out to be correct, just not the way you thought.
Whydening Gyre
5 / 5 (4) Sep 18, 2017
Exactly the same mistake Schneibo makes, trying to subject an electro-magnetic wave to the Law of Physics of kinetic energy, treating an EM wave as if it were a particle of mass.

Don't nuclear techs agree - a photon has a relativistic mass?
If you transfer the relativistic mass of a forward moving photon into a spin motion...
Wouldn't that still retain the mass? (Not to mention - the speed...)
Whydening Gyre
5 / 5 (4) Sep 18, 2017
I'm glad you guys are fighting and nobody picked up on my typo about Einstein's wife always going the same speed. I guess she was the light of his life?

From a Relative standpoint - she did...:-)
Hyperfuzzy
1 / 5 (1) Sep 18, 2017
You guys need more detail about everything you profess to know or even don't know. Anyway, it was probably his first wife's idea, relativity. Not to be degrading, with what was known, she had not done her homework. Kicked out of school. OK, I get the speed joke; but, if you laugh, the jokes on you. Get it!

No matter what the density, there are only two items present at a number that allows the state to exist, i.e. initial relative motion, initial densities, ... However, it must obey the rules when stacking! Stop with this "The physics of symbolgy"!
Da Schneib
5 / 5 (3) Sep 18, 2017
@Whyde, photons have momentum, not mass.
dnatwork
1 / 5 (4) Sep 18, 2017
The place where I see you talking past each on density is this:
One side says sufficient density will produce the gravity needed even with a smal mass.
The other side asks how could you get that much density?
The first side says by having enough gravity.
Oops.

The second side asks where does that gravity come from?
The first side says by having a lot more mass.
Oops.

The first side is being circular. It seems like they are pointing out things that are true in isolation about a system that contains all those things at once, but they keep losing track of the fact that the question was about what is true in a system where only one of those things is present, in isolation from those other things.

The second side keeps asking and quoting instead of pointing out the illogic of the argument, that has nothing to do with physics and everything to do with changing the question instead of answering it directly.

Everybody loses. Yay!
Hyperfuzzy
1 / 5 (1) Sep 18, 2017
Einstein's dissertaion was on "particles", etc. so, why not make light a set of pores, ... Logic?

Planck confuses me, mathematical but ignores the fact that the Quamtum may be defined; the idea that the math always defines some wave equation doesn't mean Schroendingers cat is alive or dead; however, does beg the question if it can be defined with a set of wavelets defining certainty. I always sought this as my answer to "is the cat alive or dead?
dnatwork
1 / 5 (4) Sep 18, 2017
Again, Benni...
When is gravity NOT dependent on the density of mass?
...... it's another one of your suppositions, prove it.

Take a 2 inch diameter ball of styrofoam. Drop it on your foot.
Take a 2 inch ball of lead. Drop it on your foot.
You need a further example?


That's momentum, not gravity. Both objects are accelerated the same by earth's gravitational field, but the lead ball picks up more kinetic energy. The reason it hurts is not because it generates more gravity on its own, as you imply.
Hyperfuzzy
1 / 5 (1) Sep 18, 2017
You can always define it with an n'th order polynomial stuck into a location you wish to examine, no matter the scale, you'll find a set of wavelets that might fit a theory; however can the wavelets describe the object with simulation, using measured data as feedback. I'll wait. Then ask the system to make requests, and gives proper instruction. Why aren't we there?
Da Schneib
5 / 5 (2) Sep 18, 2017
See, @dnat, this is why I am not bothering. You misrepresent anything you disagree with as a "circular argument." Misrepresentation of opposing arguments is a hostile act.
dnatwork
1 / 5 (4) Sep 18, 2017
I have brought ideas but they've been rejected out of hand.
No, evidence has been presented that they were wrong, and not all of them- your deepest idea turned out to be correct, just not the way you thought.


Okay, I saw same observations (accelerating expansion) being pointed to, not evidence of what is the right interpretation. Saying that dark energy is the way those observations are explained by current theory begs the question. Literally. I started by asking aren't there other ways to interpret these observations. It really seemed like you were pointing to the observations and the theory and saying each proves the other because that's how it is in the theory.

Again, I don't understand enough of the math. I'm reacting to the words in English.

Cont'd.
Uncle Ira
4.2 / 5 (5) Sep 18, 2017

That's momentum, not gravity. Both objects are accelerated the same by earth's gravitational field, but the lead ball picks up more kinetic energy. The reason it hurts is not because it generates more gravity on its own, as you imply.


Okay smarty pants. Stand on an earth sized Styrofoam ball and drop a 2 inch lead ball on your foot. Then try it on the earth sized earth. What? You did not feel the difference?
dnatwork
1 / 5 (4) Sep 18, 2017
On "consistent frame of reference," I think that means the photon emitted somewhere else does not exist in my frame of reference until it gets here. That delay is the only way for redshift to occur. That's the only way it can be emitted as a blue photon everywhere but beperceived as some other color in different frames. That's the only way galaxies can appear to move away faster than the speed of light. For the frame to be internally consistent, it cannot encompass everything without breaking all the laws of physics.

Also, a frame cannot arbitrarily exclude that which defines the system in question. The middle of a supernova cannot be said to have great density while ignoring all the mass around it in the same star. That's just as inconsistent as including a star from three galaxies over.

That's what I understand about frames. If you say no, I still don't get it, then we both know where the other stands.
dnatwork
1 / 5 (4) Sep 18, 2017
See, @dnat, this is why I am not bothering. You misrepresent anything you disagree with as a "circular argument." Misrepresentation of opposing arguments is a hostile act.


Read back and check the representation. It's all here in this thread. You said sufficient density would create a black hole a small mass. Benni said what's density got to do with it? Someone chimed in about the slope of a gravity well. I asked what would compress the small mass to that density. Someone said lots of gravity. I asked where does that come from? (Remember, we started with absence of large mass.) You said middle of a supernova. I said that's a lot of mass, you can't exclude that from the frame of reference to win the pint about density. You said I still don't get frames.

I'm just reading the English here, no math involved. I'm pretty good at languages. Care to challenge me on formal linguistics?

Whatever. I know what I read. I think the rest of you are just here to fight strangers.
Da Schneib
5 / 5 (2) Sep 18, 2017
@dnat, I think you're the one who's here to fight strangers. All your arguments come out to be strawmen based on your own suspicions. Classic conspiracy theory syndrome.
dnatwork
1 / 5 (4) Sep 18, 2017

That's momentum, not gravity. Both objects are accelerated the same by earth's gravitational field, but the lead ball picks up more kinetic energy. The reason it hurts is not because it generates more gravity on its own, as you imply.


Okay smarty pants. Stand on an earth sized Styrofoam ball and drop a 2 inch lead ball on your foot. Then try it on the earth sized earth. What? You did not feel the difference?


You changed the question again, like I said above. You started with a straw man and then just flipped it completely. Of course the earths gravity is more than that of a styrofoam ball . That's not even trying to argue.
Da Schneib
5 / 5 (3) Sep 18, 2017
@Ira shoots... he scores! With a styrofoam ball. ;)

That's momentum, not gravity. Both objects are accelerated the same by earth's gravitational field, but the lead ball picks up more kinetic energy. The reason it hurts is not because it generates more gravity on its own, as you imply.
Okay smarty pants. Stand on an earth sized Styrofoam ball and drop a 2 inch lead ball on your foot. Then try it on the earth sized earth. What? You did not feel the difference?
You changed the question again, like I said above. You started with a straw man and then just flipped it completely. Of course the earths gravity is more than that of a styrofoam ball . That's not even trying to argue.
But the point is, density matters to gravity. Like I said, you're just here to argue.
dnatwork
1 / 5 (4) Sep 18, 2017
@dnat, I think you're the one who's here to fight strangers. All your arguments come out to be strawmen based on your own suspicions. Classic conspiracy theory syndrome.


Straw man is setting up a caricature of the opposing position and attacking that instead of what was actually said. I'm quoting you all in the same thread, as I recall the discussion the last few days. Anyone can check it.

Conspiracy theory would be if I thought the man was out to get us, hiding the truth, etc. I'm saying I don't dispute the observations, I wonder about the twists and turns that have led the theory to things like dark energy and dark matter. Things where the only possible proof of their existence is the initial observation because the explanation, at least as received by poor laymen eating bullshit, is that they can't interact with normal matter or occur anywhere near us. It's fishy, I don't have to like it. It's the internet, we all get to be wrong. I'm just not insisting I'm right
Da Schneib
5 / 5 (2) Sep 18, 2017
Here, let's look at the math:

F(g) = Gmm'/r²

That r applies up until you get to the surface (radius) of a body; after that it starts to decrease. This is due to something called the "shell theorem" which, like the EFE, SRT, and many other things you can look up on Wikipedia.

Of course that depends on whether you're actually looking to learn something (i.e. read Wikipedia) or just here to litigate (i.e. a troll).
Uncle Ira
4.2 / 5 (5) Sep 18, 2017
You changed the question again, like I said above. You started with a straw man and then just flipped it completely. Of course the earths gravity is more than that of a styrofoam ball . That's not even trying to argue.


Well from here it looks you are the Skippy trying to argue, and you are really bad at it. How the heck I can "change the questions again"? When I did not change him even the first time?

The question was whether gravity is dependent on density. Or is not depending on density. All I did was point out the example that even a couyon could understand to show that density of what you are standing on has a lot to do with how much gravity you are going to experience, eh?

Laissez les bons temps rouler Skippy. (That's coonass for: "Now you can put on your well earned silly looking pointy cap and sit over there in the corner.")

dnatwork
1 / 5 (4) Sep 18, 2017
But the point is, density matters to gravity. Like I said, you're just here to argue.

I'm only insisting on consistency from one comment to the next.

Nobody said density and gravity were unrelated. The statement that was being challenged was that you could create a black hole by bringing a small mass to sufficient density. The only way to do that, as you all have come around to saying, is by having the small mass inside a large mass that generates the gravity to create the required density.

How is that not circular? How is it consistent? We started by talking about a small mass, it got changed to a large one. No one would have challenged the idea that a large mass has high gravity and high density, not even Benni.

It was setup for an argument that spun around and went nowhere. There was no effort to stick to the question, it just kept changing.

My pointing that out does not make me a conspiracy theorist.
Da Schneib
5 / 5 (2) Sep 18, 2017
You really gotta love it when math from 1687 proves you right.

Nobody said density and gravity were unrelated.
That was your quote @Ira was responding to, @dnat. If you didn't mean it that way, why did you say it?
Da Schneib
5 / 5 (2) Sep 18, 2017
I gotta ask, @dnatwork: #atwork, are you a lawyer? Second choice, philosopher or social scientist? Third choice, critic (art, show, or book)? Fourth choice, reporter with no science education?
Da Schneib
5 / 5 (2) Sep 18, 2017
As far as "small mass," define what you mean. Below the limits of the fluctuation theorem, we don't know how small masses behave with respect to gravity. It's not been measured. Above that limit, yes, they form black holes. Any statement about how masses below the limits of the FT behave with respect to gravity are rank speculation. It's the line between classical and quantum behavior. And we have no quantum theory of gravity.
Uncle Ira
4.4 / 5 (7) Sep 19, 2017
I'm only insisting on consistency from one comment to the next.


Cher that was two mistakes in one. Insisting is a couyon's game. And this is the physorg, "consistency from one comment to the next" never was, is not now and probably never will be a driving force here.

It don't matter if you insist or wish or buy or beg, so maybe you can find some other place where they will cater to your "insisting".

Oh yeah, I almost forget. If you go out to find some other place to try your "insisting" be sure to leave your silly looking pointy cap at the door so the next couyon does not have to do without one.
dnatwork
1 / 5 (4) Sep 19, 2017
Hmm. We have different standards of proof. Pointing to the formula and taking about radius does not prove anything about density or styrofoam balls. It's just a formula.

And r stands for the distance between the centers of two masses, not the distance to the surface of one of one body. I checked Wikipedia, you can look it up too.
Da Schneib
5 / 5 (2) Sep 19, 2017
Yes, we do have different standards of proof. I believe what the math tells me, and Newton's 1687 Law of Universal Gravitation says radius matters, and the formulae for density and volume say it matters too. This is basic math. It shows how physical reality behaves.

Sir Edmund Halley proved that when he used Newtonian TUG to correctly predict the return of his eponymously named comet.
dnatwork
1 / 5 (4) Sep 19, 2017
You really gotta love it when math from 1687 proves you right.

Nobody said density and gravity were unrelated.
That was your quote @Ira was responding to, @dnat. If you didn't mean it that way, why did you say it?


Uh, no. Ira was responding to Benni. He even named Benni in the response.

And originally it was Benni who said "what's density got to do with it?" And it was clear he was not saying gravity and density are unrelated. He was challenging the statement just prior, that a small mass could become a black hole if it had sufficient density.

I joined in to point out that you could achieve such density with a small mass only if you added more energy than is available. You said you could do it at the center of a supernova. But that's not a small mass anymore, and it's already high gravity, so it's silly to claim that proves any point about density and gravity in the absence of mass, which was the original claim.
Da Schneib
5 / 5 (2) Sep 19, 2017
I mean, really, you're arguing with math from freakin' 1687? Really? Really?

I suppose I shouldn't be surprised you've never heard of the FT.
dnatwork
1 / 5 (4) Sep 19, 2017
I'm not arguing with Newton. I'm saying that formula says nothing about density. The r stands for the distance between the centers of two masses, not the radius of any single mass. There is no term there that describes the radius of either mass and therefore it cannot be used to address any question of density.

Saturn is less dense than water. Do you think it has less gravity than the earth? No, you know better. The relationship is more complicated.

How do you keep getting mad at me for not knowing the math? That's just about the first thing I said.

I've heard of field theory. That's advanced math. See above.
Da Schneib
5 / 5 (2) Sep 19, 2017
I'm saying that formula says nothing about density.
Only if you ignore the formulae for density and volume. Which it's not reasonable to deny.
dnatwork
1 / 5 (4) Sep 19, 2017
Look, I'll give you the example about density that actually proves your point about small masses without being circular.

We have to have a small mass, not absurdly small, that is isolated from other mass so that we're not cheating with arbitrary reference frames. We also can't have it in a large gravity field, also cheating. Let's pick some interstellar dust, big enough to see with the naked eye.

Now we need some energy input to compress it, like I said way back, but not from this bit of mass or anything close enough that it could be construed as part of the same system. How about a supernova a light year away? Make it two, one on either side.

The shockwaves from the supernovae slam into the dust simultaneously, compressing it to great density, which increases the slope of its gravitational field tremendously. If black holes exist, this speck of dust becomes one.

Consistent with logic, physics, and what was said originally without changing it just to win.

See now?
Da Schneib
5 / 5 (2) Sep 19, 2017
Those supernovae would have to be really, really close. What happens in a supernova that creates a black hole is something that happens right in the middle of the explosion. It's an implosion of the inner layers driven by the detonation of the outer layers.

I'm not sure what you want me to see here. While what you postulate is possible, it is incredibly unlikely. Also, black holes that small don't last long; they evaporate by Hawking radiation.

The FT is not field theory. It's the Fluctuation Theorem. I suggest you look it up.
dnatwork
1 / 5 (4) Sep 19, 2017
I'm saying that formula says nothing about density.
Only if you ignore the formulae for density and volume. Which it's not reasonable to deny.


You didn't quote those formulas. They are not related to gravity in their own terms, either.

What's unreasonable is your snipping out my point about Saturn. Low density, high gravity. Direct counter example to your claim. You tried to slip past by making a false claim about some other formulas. This stuff is transparent.

Frankly, the lead ball was already a strong counter example because it was high density and low gravity, but that's why what's his name started calling me stupid. Before you tag teamed back in. Trying to find the least respectable line of work for me? You could have just called me a whore. Save some time.

Actually it's like arguing with my ex-wife. Terms of debate constantly slipping around. Claims made and denied, insults thrown. Good times.
dnatwork
1 / 5 (4) Sep 19, 2017

I'm not sure what you want me to see here. While what you postulate is possible, it is incredibly unlikely.

Exactly what I said, it's unlikely. But it was chosen to prove your point, in some possible circumstance, without contradicting any of the conditions you yourself placed with your initial claim, nor most of the conditions placed by others. Benni rejects black holes, so that's a different kind of argument to be had.

What I wanted to show was how to build a consistent argument without changing the terms of the debate. Also while staying within the bounds of physics and respecting reference frames, but none of you can even talk about that because you throw insults first.

The FT is not field theory. It's the Fluctuation Theorem. I suggest you look it up.


Fine. You know this started on Thursday. Was I supposed to get two PhDs over the weekend, between laundry and putting my cat to sleep?

This whoreson carpetbagger art critic (that was low) is tired.
Da Schneib
5 / 5 (2) Sep 19, 2017
I'm saying that formula says nothing about density.
Only if you ignore the formulae for density and volume. Which it's not reasonable to deny.


You didn't quote those formulas. They are not related to gravity in their own terms, either.
So you are not familiar with the formula for spherical volume? Seriously?

I won't even mention the formula for density. It's obvious from the units.
dnatwork
1 / 5 (4) Sep 19, 2017
4 pi r cubed? Mass over volume?

Go back to Newton's gravity. That is not the same r. Newton's r is the distance between two masses. It's the radius of the orbit, not the distance between surface and center of a given mass. Different measurements, same symbol.

Putting the two formulas next to each other (which you didn't actually do, by the way) does not in itself prove a relation of density to gravity because the units are different.

What about Saturn?

This is what I meant earlier about pointing to formulas and treating that as proof. Counter examples from the real world aren't overruled by formulas, they prove bad conclusions wrong, despite any formula behind the conclusion. Who said that Einstein said observations trumps theory? Maybe all of you did.
Da Schneib
5 / 5 (2) Sep 19, 2017
That is not the same r.
I don't know what that means.

That formula of Newton's works right on the surface of the Earth; plug in the radius of the Earth, your mass, the Earth's mass, and you have the exact force of gravity you feel: 9.8 Newtons per kilogram. Now reduce the radius of the Earth; what force do you feel?

How come the radius of you doesn't matter? Well, that would be because you're only two meters high and the Earth is thousands of kilometers wide. Your size is swamped. <-that's one of those mathematical terms you're not comfortable with.

I see no further point in this. You're obviously totally out of your depth mathematically. You'll need to learn enough math to be able to do fractions and algebra in order to understand any of this; you simply can't see the relationships well enough. "Different r" indeed.
dnatwork
1 / 5 (4) Sep 19, 2017
@RealityCheckThat is a sensible approach to science discourse, mate; keep it up in all your discussions. :)

However, your/DS's foregoing discussion/points are NOW MOOT; no longer seriously held by mainstream science NOW DISCOVERING NEW things; and bravely REVIEWING ALL Big-Bang-related claims objectively.

Since there was/is NO Big Bang OR Inflation OR Expansion/Accelerated Expansion, it is futile to argue claims/explanations which have NO MEANING.

OK? :)



Thanks for the support!
dnatwork
1 / 5 (4) Sep 19, 2017
That is not the same r.
I don't know what that means.

That formula of Newton's works right on the surface of the Earth; plug in the radius of the Earth, your mass, the Earth's mass, and you have the exact force of gravity you feel: 9.8 Newtons per kilogram. Now reduce the radius of the Earth; what force do you feel?

How come the radius of you doesn't matter? Well, that would be because you're only two meters high and the Earth is thousands of kilometers wide. Your size is swamped. <-that's one of those mathematical terms you're not comfortable with.

I see no further point in this. You're obviously totally out of your depth mathematically.... "Different r" indeed.


You chose a special case as proof of all cases. Is the orbit of earth equal to the radius of the sun? No. Does the formula work? Yes. Different r.

And so many insults.
Da Schneib
5 / 5 (2) Sep 19, 2017
Go away, lawyer troll. If you can't see the difference between the surface of the Sun and a position 93 million miles away, you're too stupid to be worth talking to. And sorry, that also is not ad hominem; you just demonstrated it.
dnatwork
1 / 5 (4) Sep 19, 2017
Huh. I actually found his comments very heplful and kind at first.

The turning point was obvious at the time, as soon as I agreed with Benni about something. But everybody is right about some things and wrong about others. Folks should chill about being the only one who could be right about everything. Even your enemy is right occasionally.

I'm pretty sure I know which r Newton had in mind. He wouldn't have used swamping. Likewise on redshift and frames of reference. I'll just go back to thinking and reading.
Da Schneib
5 / 5 (2) Sep 19, 2017
Trolls of a feather grex together.
Kron
5 / 5 (2) Sep 19, 2017
There is so much nonsense in the comments above, so much misunderstanding. I thinkmost posters above need return to the basics of what theories and models are. Theories and models are able to take real-world observations and work with them to produce outcomes that match those seen in the real-world. There is nothing more to it than that. The possible correct theories are infinite, we choose to use the theory which is easiest to use (Occam's razor).

Dark Matter and Dark Energy are required (not entirely, other solutions exist) for the standard model of the cosmos to work. There are possible, and indeed models in existence that require no Dark Energy and Dark Matter.

When creating a theory some assumptions must be made. From first principles formulations emerge.
Kron
5 / 5 (1) Sep 19, 2017
Einstein famously said: if facts don't fit theory, change the facts.

Most people think this is funny, like some kind of joke. Literally, the tenets of theories are assumptions taken as true, factual. If a theory doesn't fit those facts, you can go back and reexamine your tenets. You can change what you assumed to be a fact and your theory might be fixed.
Benni
1 / 5 (7) Sep 19, 2017
So you are not familiar with the formula for spherical volume? Seriously?

I won't even mention the formula for density. It's obvious from the units.


What gets totally lost by Schneibo in the entire argument about density dependent gravity versus mass dependent gravity is the fact that TOTAL GRAVITY of a constant mass does not change by changing it's volume. The only thing that can change is NET FORCE per unit area of the force being exerted at the surface of the mass, this by necessity changes when a constant quantity of a mass EXPANDS or CONTRACTS.

Schneibo, I learned this in junior high school, there is no free lunch. It isn't possible to get more out of a closed system than what is put into it, otherwise it's perpetual motion & that is your calling card.
Hyperfuzzy
1 / 5 (2) Sep 19, 2017
Try changing the locations of the protons and the electrons. Else shut up!
Whydening Gyre
4.2 / 5 (5) Sep 19, 2017
Again, Benni...
When is gravity NOT dependent on the density of mass?
...... it's another one of your suppositions, prove it.

Take a 2 inch diameter ball of styrofoam. Drop it on your foot.
Take a 2 inch ball of lead. Drop it on your foot.
You need a further example?


That's momentum, not gravity. Both objects are accelerated the same by earth's gravitational field, but the lead ball picks up more kinetic energy.

Because it has more MASS (weight, not size) due to -- density. Therefore has a stronger gravitational field of it's own. I think you might be thinking ofmass as volumetric in nature.
The reason it hurts is not because it generates more gravity on its own, as you imply.

It is EXACTLY that. Because of the density/mass increase in a lead ball, it will exhibit more "weight" (gravity) per square (insert your preferred measuring increment here) at it's surface.
Whydening Gyre
4.2 / 5 (5) Sep 19, 2017
@Whyde, photons have momentum, not mass.

Which is why I was careful to say "relativistic" mass, not invariant...
Whydening Gyre
4.3 / 5 (6) Sep 19, 2017
@Whyde, photons have momentum, not mass.

Which is why I was careful to say "relativistic" mass, not invariant...


And... an earth sized styrofoam ball is still gonna have a good sized mass (weight). That 2" lead ball is still gonna hurt when it hits your foot...
dnatwork
1.8 / 5 (5) Sep 19, 2017
Because it has more MASS (weight, not size) due to -- density. Therefore has a stronger gravitational field of it's own. I think you might be thinking ofmass as volumetric in nature.
The reason it hurts is not because it generates more gravity on its own, as you imply.

It is EXACTLY that. Because of the density/mass increase in a lead ball, it will exhibit more "weight" (gravity) per square (insert your preferred measuring increment here) at it's surface.


Weight is not mass. It is the measurement of downward force exerted by a unit of mass in a given gravitational field. Hence you are weightless in space, but you lose no mass.

The density of the lead ball is irrelevant. Take that lead and melt it, then form it into a hollow ball 3 inches across. The density will be cut by two-thirds or more, but the mass is unchanged. Drop it on your foot, and it strikes with the same force as before, hurts just a much. Because the formula is mv^2. No term for density.
dnatwork
1.8 / 5 (5) Sep 19, 2017
Did you really say the gravity generated by the lead ball is the reason it hurts your foot? No, it's gravity generated by the earth acting on the lead ball to accelerate it until it hits your foot. The mass of the lead times the velocity squared equals the force of the impact.

You are clearly the one thinking that mass is volumetric.

The only way that makes any sense is if you are looking at the level of the atom. There I would agree, the density of the lead atom makes it heavier than the styrofoam nucleus. (Don't even object to styrofoam atoms; it's element 7.5 on the periodic table.) But the only reason it's denser is because there is more mass (more protons and neutrons contributing mass) in the nucleus. The nucleus of lead may not even be any denser than some other kind of atom; who knows? It's more about the overall volume of the atom including the electron shells, so it's mostly empty space anyway.

Still no answer on Saturn.
Benni
1 / 5 (6) Sep 19, 2017
Because the formula is mv^2


KE=1/2mv²............hate to interrupt a good Comment, but......
dnatwork
1.8 / 5 (5) Sep 19, 2017
Because the formula is mv^2


KE=1/2mv²............hate to interrupt a good Comment, but......


My bad. This is high school physics, which is the last time I saw any of the formulas.

Doesn't change the fact that there is no term for density or volume in the formulas in question, and the r in Newton's gravity is the radius of the orbit not either of the objects.
dnatwork
1.8 / 5 (5) Sep 19, 2017
I came here stating flat out I was mostly ignorant, but I'm having to explain middle school physics to the guys who claim I don't get it? Wow.

The ira- troll-skippy-fake Cajun-whatever was right. I can't insist on anything.

However, I can choose to engage only with people who agree to abide by common rules of argumentation and logic, who don't conflate units and misconstrue basic physics in order to score internet points. Lesson learned.
Whydening Gyre
4.3 / 5 (6) Sep 19, 2017
I came here stating flat out I was mostly ignorant, but I'm having to explain middle school physics to the guys who claim I don't get it? Wow.
The ira- troll-skippy-fake Cajun-whatever was right. I can't insist on anything.

Please do not insist I am claiming you don't get it...:-)
I am an artist, higher math not being in my tool kit, either.
However, I can choose to engage only with people who agree to abide by common rules of argumentation and logic,

Which, in my experience, can often be a subjective interpretation...
who don't conflate units and misconstrue basic physics in order to score internet points. Lesson learned.

Perhaps other people are having a tough time translating lay verbage into a framework that they've been schooled in. The conflating and misconstruction can possibly be a result of that...
BTW - gravitational momentum is a product of BOTH gravitational entities, not just the larger one...:-)

Benni
1 / 5 (6) Sep 19, 2017
BTW - gravitational momentum is a product of BOTH gravitational entities, not just the larger one
.

Yeah, but the lead ball landed on the top your foot due to "the larger one". If it hadn't you would have felt a hit at the bottom of your foot by the Earth the weight of which would have crushed you in an instant.
Whydening Gyre
4.3 / 5 (6) Sep 19, 2017
Did you really say the gravity generated by the lead ball is the reason it hurts your foot?

No , I did not. That is deliberate misconstruction. It's the COMBINED interaction that hurts your foot.
Why doesn't the styrofoam one of the same volume do the same? Density is the easiest word, even if maybe not the most correct (mass) for you.
... the density of the lead atom makes it heavier than the styrofoam nucleus.

GASP - you said the "D" word!
(Don't even object to styrofoam atoms; it's element 7.5 on the periodic table.)

Humour. I get it.
But the only reason it's denser is because there is more mass (more protons and neutrons contributing mass) in the nucleus.

(And the molecular lattice may be tighter.)
The nucleus of lead may not even be any denser than some other kind of atom; who knows?

Uranium (92), fer instance?
Benni's a Nuclear Engineer, he should be able to field that one...
..

Whydening Gyre
4.3 / 5 (6) Sep 19, 2017
BTW - gravitational momentum is a product of BOTH gravitational entities, not just the larger one
.

Yeah, but the lead ball landed on the top your foot due to "the larger one". If it hadn't you would have felt a hit at the bottom of your foot by the Earth the weight of which would have crushed you in an instant.

There ya go, Dnat. THAT is deliberate misconstruction.
(One of Benni's favourite pastimes.)
Notice how he missed the part about the fact that you are moving at the same momentum of earth(relative the lead ball). Not to mention how that Earths gravity is expressed (equally) over a much larger surface area...
Whydening Gyre
4.3 / 5 (6) Sep 19, 2017
The density of the lead ball is irrelevant. Take that lead and melt it, then form it into a hollow ball 3 inches across. The density will be cut by two-thirds or more, but the mass is unchanged. Drop it on your foot, and it strikes with the same force as before, hurts just a much. Because the formula is mv^2. No term for density.

YEah, but...
If ya wanna be precise, you have increased the surface area. Ergo, the ball's relative gravity (combined with Earth's) is felt over a larger area. Therefore, the force striking your foot per (insert your preferred measuring metric here) is slightly lower.
But... Prob'ly hurt more since it hit a larger area. (Lead is still pretty dense, after all...)
Benni
1 / 5 (6) Sep 20, 2017
If ya wanna be precise, you have increased the surface area. Ergo, the ball's relative gravity (combined with Earth's) is felt over a larger area. Therefore, the force striking your foot per (insert your preferred measuring metric here) is slightly lower.
But... Prob'ly hurt more since it hit a larger area. (Lead is still pretty dense


So how does any of this prove TOTAL GRAVITY in a closed system with constant mass changes with increasing or decreasing volume? Instead of discussing that, you are way off on twiggy issues that have nothing to do with proving gravity is density dependent as opposed to mass dependent. You must be an artist, Schneibo as well.
dnatwork
1 / 5 (3) Sep 20, 2017
If you can't agree on basic terms (debate, definition of density, whether parts of a theory can be regarded as evidence for other parts of the theory), don't engage.
Hyperfuzzy
1 / 5 (1) Sep 20, 2017
If you can't agree on basic terms (debate, definition of density, whether parts of a theory can be regarded as evidence for other parts of the theory), don't engage.

Daily Comics!
jonesdave
4.2 / 5 (5) Sep 20, 2017
If ya wanna be precise, you have increased the surface area. Ergo, the ball's relative gravity (combined with Earth's) is felt over a larger area. Therefore, the force striking your foot per (insert your preferred measuring metric here) is slightly lower.
But... Prob'ly hurt more since it hit a larger area. (Lead is still pretty dense


So how does any of this prove TOTAL GRAVITY in a closed system with constant mass changes with increasing or decreasing volume? Instead of discussing that, you are way off on twiggy issues that have nothing to do with proving gravity is density dependent as opposed to mass dependent. You must be an artist, Schneibo as well.


And you are an idiot. As proven. Give up Benni boy. Yes? You know s*** about science, do you, love? Absolutely clueless. N'est-ce pas?
Benni
1 / 5 (4) Sep 20, 2017
And you are an idiot. As proven. Give up Benni boy. Yes? You know s*** about science


Just one more foul mouthed name calling rant from another of the PERPETUAL MOTION CROWD living here.
Benni
1 / 5 (4) Sep 20, 2017


And you are an idiot. As proven. Give up Benni boy. Yes? You know s*** about science, do you, love? Absolutely clueless. N'est-ce pas?


I notice Schneibo gave you a 5 Star for that foul mouthed rant. Yep, the PERPETUAL MOTION crowd here all stick together like birds of a feather.
Ojorf
4 / 5 (4) Sep 21, 2017
Benni Bluster, I see you get voted all 1's, in line with the content of your comments.

You really need to do some elementary reading, the basics, no math, nothing older than 2 decades.
I suggest Hawkins and Green and Gribbin etc. (pop science)
You are so far off on the basics of science and continually argue about small details totally out of context.
It would really give you the foundation you need.
Whydening Gyre
4.2 / 5 (5) Sep 21, 2017
So how does any of this prove TOTAL GRAVITY in a closed system with constant mass changes with increasing or decreasing volume? Instead of discussing that, you are way off on twiggy issues that have nothing to do with proving gravity is density dependent as opposed to mass dependent. You must be an artist, Schneibo as well.

Sigh.. nobody is saying the total gravity changes. A given mass is the same regardless of volume. However, it does change the variables of the Inverse square law and subsequently how 2 bodies interact.
Try this link for a better comprehension;
https://en.wikipe...uare_law
along with this one;
https://en.wikipe.../gravity
Combined they give a pretty decent explanation.
Whydening Gyre
4 / 5 (4) Sep 21, 2017
And you are an idiot. As proven. Give up Benni boy. Yes? You know s*** about science, do you, love? Absolutely clueless. N'est-ce pas?

Actually, JD, I don't think he's clueless as it appears. He does, however, appear to be deliberately misconstruing common understanding.
Ergo - trolling.
Whydening Gyre
4.2 / 5 (5) Sep 21, 2017
If you can't agree on basic terms (debate, definition of density, whether parts of a theory can be regarded as evidence for other parts of the theory), don't engage.

Then you might consider practicing what you preach...
Discussions like this are (ideally) meant to find and agree on, those "basic terms"...
But, we will always encounter those, unwilling or unable, to participate in that discussion reasonably...
Benni
1 / 5 (4) Sep 21, 2017
nobody is saying the total gravity changes. A given mass is the same regardless of volume. However, it does change the variables of the Inverse square law and subsequently how 2 bodies interact.
......you don't even know what it is you just wrote about applying the Inverse Square Law.

Decrease the volume of space that a constant given mass occupies & the Inverse Square Law adjusts proportionately & gravitational attraction between the two bodies decreases simply because the distance between the two bodies increased. Tough math I know WhyGuy, but it's simply a fact of Fundamental Physics, just one more thing those of you in the PERPETUAL MOTION crowd living here are unable to figure out.
Benni
1 / 5 (4) Sep 21, 2017
You really need to do some elementary reading, the basics
.......and you should do that, try this for example:

"Decrease the volume of space that a constant given mass occupies & the Inverse Square Law adjusts proportionately & gravitational attraction between the two bodies decreases simply because the distance between the two bodies increased."

Ojorf
5 / 5 (4) Sep 21, 2017
You proved my point!!!
Uncle Ira
5 / 5 (3) Sep 21, 2017
You proved my point!!!

But did you really think there was a snowball's chance he knew what he was talking about? No wonder needs to snip & glue of Einstein-Skippy's stuff to pretend he knows this stuff.

"Decrease the volume of space that a constant given mass occupies & the Inverse Square Law adjusts proportionately & gravitational attraction between the two bodies decreases simply because the distance between the two bodies increased."


@ Bennie-Skippy. That is what you really need to use your snip & glue with, you are not ready for Einstein-Skippy. You really drop the ball on that one Cher. And since I can't find a way that it could possible be a typo we can only think it was a the most basic physics thing you should have learned in high school but did not.
dnatwork
1 / 5 (2) Sep 21, 2017
Sigh.. nobody is saying the total gravity changes. A given mass is the same regardless of volume.


Sorry, that is what they seemed to be saying with the comments about greater density leading to an increase in gravity.
Da Schneib
5 / 5 (1) Sep 21, 2017
I think what amazes me most is that #physicscranks expect the same mass to have a different gravity in the far field, and a different density to have the same gravity in the near field.

It's like #physicscranks are totally immune to the ideas of density and gravity. Oh, wait....
Uncle Ira
5 / 5 (3) Sep 21, 2017
Sorry, that is what they seemed to be saying with the comments about greater density leading to an increase in gravity.


Don't be sorry Cher. Be curious and learn. And before you try to overturn Newton, Kepler, Einstein, Hooke, et al, you first got to come to grips with a thing called First Principles.

An object the size of the earth with 2 times the density of the earth will have 2 times the gravitation. Mass per unit of volume is how density is defined, that is a First Principle. If you double the mass in a given volume, you double the density AND you double the gravitation, another First Principle.

Where Bennie-Skippy dropped the ball is he thinks the inverse square law says something about the radius of a gravity producing body. It does not. The inverse square law pertains to the distance between the two centers of gravity.

Before you can take off your silly looking pointy cap you got read up on Newton's gravitation, mass, radius, and density,
Uncle Ira
5 / 5 (3) Sep 21, 2017
It's like #physicscranks are totally immune to the ideas of density and gravity. Oh, wait....


Well what can you do Cher? If they think they understand something, it's our fault they misunderstand. (And some peoples just want to argue.)
dnatwork
1 / 5 (2) Sep 21, 2017
Ugh. First it was small mass that somehow gained density, and the density generated more gravity. How did it gain density? In a high gravity field. How did that happen (without being circular)? It was inside a much larger mass. So it was not a small mass anymore.

Now it's the earth. Somehow reduce the radius of the earth to increase its density, and the gravity at the surface will increase. But that's not total gravity, and how do you reduce its radius anyway? Oh, just double its mass but keep the same radius, so the density doubles and so dues the gravity.

Every time, you (plural) have meandered around until you try to sneak in a huge increase in mass. That's the only way to increase total gravity, and at some level you know it.

Did Benni have a brain fart just now. Maybe. But who hasn't? it it was da Schneib who said exactly the same thing about r the other day. Heat of battle.

Walk away.
Uncle Ira
5 / 5 (2) Sep 21, 2017
Somehow reduce the radius of the earth to increase its density, and the gravity at the surface will increase.


Somehow that is just wrong. Cher, ask the Google-Skippy if he has time to show you something about Newton's "Shell Theorem".

Oh, just double its mass but keep the same radius, so the density doubles and so dues the gravity.
Now you are starting to get it. I knew you could Cher.

Every time, you (plural) have meandered around until you try to sneak in a huge increase in mass. That's the only way to increase total gravity, and at some level you know it.
I understand that just fine. That is what we been trying to help you with. If you double the mass of the earth, and multiply the volume by 10 times, you are going to feel less gravity at the surface.

Uncle Ira
5 / 5 (2) Sep 21, 2017
Did Benni have a brain fart just now. Maybe.
Bennie-Skippy is always crowing about his engineering prowess. And his maths prowess, and how awesomely he understand gravity. He posted the same thing twice in 10 minutes. And he still doesn't even understand how mass, gravity and density are related.

But who hasn't? it it was da Schneib who said exactly the same thing about r the other day. Heat of battle.
No he did not, you think he did because your are having a great time understanding the most basic stuffs and not realizing how unprepared for class you are.

So put the silly looking pointy cap back and get back in the corner and tomorrow try to have your homework done. (And don't let Bennie-Skippy help you with it or you will earn permanent title to the silly looking pointy cap.)
Da Schneib
5 / 5 (1) Sep 21, 2017
What this confusion is really all about is the near field gravity at the surface of a spherical body, and the far field a long way away from the body.

As long as the mass stays the same, you can say the "width" of the overall gravity well will stay the same; but the surface gravity, that is, you can say the "depth" of the gravity well, will change with density.

In the far field, say at the distance of the Moon, Earth's density doesn't matter; it could be half as dense as it is or twice as dense as it is, with the same mass, and the Moon would orbit just the same. But on the surface of Earth, if it were twice as dense or half as dense, it would make a lot of difference to the gravity at the surface.

This is all obvious if you know how math works, from Newton's TUG, to wit:

F(g) = Gmm'/r²

and if you know how the spherical volume formula and the formula for density work. Without this understanding of math, it's all flailing. And lawyering. And trolling.
Da Schneib
5 / 5 (1) Sep 21, 2017
Now, of course, this is all in the framework of TUG; using GRT (the EFE), there will be slight differences in the gravity field at the distance of the Moon. But these are very small effects compared with the overall gravity field of Earth, and for practical purposes can be safely ignored without making very much difference (as we see from the fact that NASA used TUG for the Apollo missions, and quite successfully). And these effects diminish the farther out into the field you get, which is why the precession of the planets' orbits around the Sun only has a detectable difference at the orbit of Mercury; by Venus you're far enough into the far field that TUG and GRT are indistinguishable (unless you have a few million years to hang around and measure it).

But there's no point trying to explain all that to a lawyering troll.
Da Schneib
5 / 5 (1) Sep 22, 2017
How far is the far field? Well, that depends on the diameter of the biggest body. Engineers use much the same sorts of ideas to determine when small variables are "swamped" by more important ones, and @Ira knows about that; it's when the effect of the small variables is about one tenth of the effect of the big one or ones. As a rule of thumb, then, when the distance (that is, r) is around ten times the diameter of the larger body, we can treat that as the far field. But this is just a rule of thumb; to get the exact effects, you always have to go back to the math. The math is where the exact relations live. Without the math, it's all flailing and spitting into the wind.
Da Schneib
5 / 5 (1) Sep 22, 2017
The moral of the story is, if you don't want to do any math at all, you're going to have to take the word of people who can do the math for it. If you want to check their results, and argue sensibly (as opposed to lawyering and trolling), then you're going to have to do at least some minimal math; by and large, this means at least algebra, trig, and maybe linear equations. You can get away without calculus for most astrophysics (and most engineering, too), but you better know those basics because otherwise you're going to look like an idiot to anyone who knows the basics, never mind a real engineer or scientist who knows the calculus. And on this forum, that means you'll get ignored, and told you're a lawyering troll, because there are enough real engineers and scientists on here to be able to tell.
Da Schneib
5 / 5 (1) Sep 22, 2017
To put it in short terms, #physicscrankscantcount. It's really just that simple.
dnatwork
1 / 5 (2) Sep 22, 2017
Here is where it actually started:
Reg Mundy - Sep 15, 2017
@Schnib
The only things that change a gravity well is the mass getting bigger or smaller, or changing density.


What's density got to do with it?


Changing an existing gravity well by means of either adding/subtracting mass or changing the density without adding/ subtracting mass. Crystal clear distinction.

The question immediately was, how do you change density independently? You need to change the mass or add a lot more energy.

The defense was as I described it.

Your misconstrual of r as radius of the larger mass (rather than distance between centers) was as I described it. I said it's not distance to the surface, it's orbital radius. You said "different r's indeed!" Now that Benni appears to have made the same mistake, you are parroting back to me what I said about r as though that's proof that you were right when you said the opposite.

Like arguing with my ex-wife. Pointless.
dnatwork
1 / 5 (2) Sep 22, 2017
Nobody can react to what you think you said. They can only respond to the meaning of the words you actually wrote. So if someone questions your meaning, don't jump down their throat. Go back and read your own words, and read them as though they came from someone else.

Do they really and necessarily and only mean what you thought you said?

Or maybe you left out a comma or an "and/or" or some other ambiguity crept in, or you flat out put the opposite word in (centrifugal instead of centripetal) and the other person is right about the words you wrote.

That does not make them right about what you meant; it only means you didn't express it correctly and now you have a chance to correct the impression you created originally.

Unless you jump down their throat and start calling names. Then you lose that chance.
Hyperfuzzy
not rated yet Sep 22, 2017
Nobody can react to what you think you said. They can only respond to the meaning of the words you actually wrote. So if someone questions your meaning, don't jump down their throat. Go back and read your own words, and read them as though they came from someone else.

Do they really and necessarily and only mean what you thought you said?

Or maybe you left out a comma or an "and/or" or some other ambiguity crept in, or you flat out put the opposite word in (centrifugal instead of centripetal) and the other person is right about the words you wrote.

That does not make them right about what you meant; it only means you didn't express it correctly and now you have a chance to correct the impression you created originally.

Unless you jump down their throat and start calling names. Then you lose that chance.

WTF?
Da Schneib
5 / 5 (2) Sep 22, 2017
How do you change density independently
If you don't have the math, you won't understand.

Nobody's proposing some magical method of changing the density. We're changing variables in an equation. It's a fairly standard thing to do just to see what the differences might be. As an example, instead of changing the density of the object, how about comparing two objects with the same mass and different densities? That proves the difference as well.

Everybody but you understood this.

Trolling lawering won't help if you don't understand math. #physicscrankscantcount.
JohnStaahle
5 / 5 (1) Sep 23, 2017
FTA;
"Dark energy is usually assumed to form roughly 70% of the present material content of the Universe."
So, since when did dark energy become "material"?!?
Since June 30, 1905.

E = m x c^2 => m = E/c^2
Hyperfuzzy
not rated yet Sep 23, 2017
FTA;
"Dark energy is usually assumed to form roughly 70% of the present material content of the Universe."
So, since when did dark energy become "material"?!?
Since June 30, 1905.

E = m x c^2 => m = E/c^2

Please stop, this is so repetitive and wrong!
dnatwork
not rated yet Sep 24, 2017
Pointless.
Da Schneib
5 / 5 (1) Oct 07, 2017
Happened to come back to this.
The question immediately was, how do you change density independently? You need to change the mass or add a lot more energy.
Ummm, you could just change the radius.

Since changing anything else in this context is ridiculous, this was obvious to anyone who knows any math at all; we're barely even talking physics, we're just talking geometry.

How did you get any kind of college education without already having known before you even got there that the same spherical mass at different densities has to have a different radius? I can't even imagine.

Pointless.
Yes, it is. If you can't do the math you can't understand the physics.
Parsec
not rated yet Oct 31, 2017
FTA;
"Dark energy is usually assumed to form roughly 70% of the present material content of the Universe."
So, since when did dark energy become "material"?!?


Since the conservation of matter and energy dictates that matter and energy are equivalent. That's when.

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