New supernova analysis reframes dark energy debate

New supernova analysis reframes dark energy debate
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.

New supernova analysis reframes dark energy debate
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
Citation: New supernova analysis reframes dark energy debate (2017, September 13) retrieved 26 May 2019 from https://phys.org/news/2017-09-supernova-analysis-reframes-dark-energy.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
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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.

Sep 13, 2017
The principle of Occam's Razor favors the model without cosmological acceleration.

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.

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(+/-)?

Sep 13, 2017
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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"?!?


Sep 13, 2017
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Sep 13, 2017
Schneibo is now oxivape.

why 1 star me?
Schneibo, for the same reason I always 1 star you.

Sep 13, 2017
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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?

Sep 13, 2017
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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.

Sep 13, 2017
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Sep 13, 2017
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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. ;)

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,

Sep 13, 2017
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Sep 13, 2017
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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.

Sep 13, 2017
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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.

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Sep 14, 2017
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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.

Sep 14, 2017
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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.

Sep 14, 2017
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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.

Sep 14, 2017
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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.

Sep 14, 2017
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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!

Sep 14, 2017
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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, ...

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.

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?

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!

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!

Sep 14, 2017
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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?"

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, ...

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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.

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?

Sep 14, 2017
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Sep 14, 2017
Whops...that worked fast. Thanks mods!

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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.

Sep 14, 2017
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Sep 14, 2017
Persistent, isn't he, our Zeph,

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.

Sep 14, 2017
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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...

Sep 14, 2017
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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.

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.

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.

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.

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.

Sep 14, 2017
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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.

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.


Sep 14, 2017
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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.


Sep 14, 2017
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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.


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

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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).

Sep 14, 2017
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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?

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.

Sep 14, 2017
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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!

Sep 14, 2017
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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?

Sep 14, 2017
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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.

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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.

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.

Sep 14, 2017
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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!

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.

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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...

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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.

Sep 14, 2017
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Sep 14, 2017
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Sep 14, 2017
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Sep 14, 2017
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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 ...

Sep 14, 2017
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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.

Sep 15, 2017
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Sep 15, 2017
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Sep 15, 2017
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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.

Sep 15, 2017
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Sep 15, 2017
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Sep 15, 2017
And he's back....and he's gone (soon-ish)

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?

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.

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.

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.

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.

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]

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!

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]

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]

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.

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]

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.

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.

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.


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.

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.

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!

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?

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.


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.

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.

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]

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]

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.

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]

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.

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]

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.

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.

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?

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.

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.

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.


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.

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*.

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.

Sep 15, 2017
Better idea, lets burn these papers.

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.

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.

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.

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?

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.

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.

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.


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.

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.

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?

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.

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.

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.

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.

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?