MOND predicts dwarf galaxy feature prior to observations

Aug 28, 2013
The predicted and observed velocity dispersions of recently measured dSph satellites of M31. Credit: arxiv.org/abs/1308.5894

A modified law of gravity correctly predicted, in advance of the observations, the velocity dispersion—the average speed of stars within a galaxy relative to each other—in 10 dwarf satellite galaxies of the Milky Way's giant neighbor Andromeda.

The relatively large velocity dispersions observed in these types of is usually attributed to . Yet predictions made using the alternative hypothesis Modified Newtonian Dynamics (MOND) succeeded in anticipating the observations.

Stacy McGaugh, professor of astronomy at Case Western Reserve, and Mordehai Milgrom, the father of MOND and professor of physics at Weizmann Institute in Israel, report their findings, which have been accepted for publication by the Astrophysical Journal, in a preprint online: http://arxiv.org/abs/1308.5894.

The researchers tested MOND on quasi-spherical, very low-surface brightness galaxies that are satellites of Andromeda. In the , they are among the smallest galaxies, containing only a few hundred thousand stars. But with conventional gravity, they are inferred to contain huge amounts of dark matter.

"Most scientists are more comfortable with the dark matter interpretation," McGaugh said. "But we need to understand why MOND succeeds with these predictions. We don't even know how to make this prediction with dark matter."

While this study is very specific, it's part of a broader effort to understand how the universe, the Milky Way and Earth formed and what it's all made of. This informs human understanding of our place in the universe, McGaugh said. Such issues have been of such importance that they've changed religion and philosophy over the centuries, sometimes sending people to be burnt at the stake.

"At stake now is whether the universe is predominantly made of an invisible substance that persistently eludes detection in the laboratory, or whether we are obliged to modify one of our most fundamental theories, the ," McGaugh continued.

The MOND hypothesis says that Newton's force law must be tweaked at low acceleration—11 orders of magnitude lower than what we feel on the surface of the Earth. Acceleration above that threshold is linearly proportional to the force of gravity—as Newton's law says—but below the threshold, no. At these tiny accelerations, the modified force law resolves the mass discrepancy.

The paper's calculations using MOND also reveal subtle differences in the gravity fields of dwarfs near and far from the Andromeda. The gravity fields of dwarfs far from the host appear to be dominated by stars within the dwarf, while the gravity fields of dwarfs close to the host appear to be dominated by the host. No such distinction is expected with dark matter.

"The influence of the host galaxy may provide a test to distinguish between dark matter and MOND," McGaugh says. "Dark matter provides a cocoon for the dwarfs, protecting the stars from tidal influence by the host galaxy. With MOND, the influence of the host is more pronounced."

In a comparison of the predictions calculated using MOND with observations of pairs of similar dwarfs, "the data appears to show MOND's prediction for the influence of the host, but it's fairly subtle," McGaugh said. MOND's predictions of the velocity dispersion were less subtle. These predictions were "really bang on," McGaugh said.

The finding bolsters the case McGaugh and Milgrom made for MOND's effectiveness in predicting properties in dwarf galaxies in a paper published earlier this year. In that paper, they successfully predicted the velocity dispersion in 17 of the galaxies.

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cantdrive85
1.7 / 5 (17) Aug 28, 2013
A modified law of gravity correctly predicted, in advance of the observations, the velocity dispersion

"It is important to understand that while a theory may permit observations, those observations do not necessarily verify the theory." Anon

"We don't even know how to make this prediction with dark matter."


"The only relevant test of the validity of a hypothesis is comparison of prediction with experience." Milton Friedman

That would be an irrelevant hypothesis then, wouldn't it.
Tuxford
1 / 5 (15) Aug 28, 2013
In LaViolette's SQK physics, blue-shifting within galaxies correlates somewhat with MOND models. Notably, in SQK, a finite distance for the influence of gravity is predicted, roughly around 10K LYrs. Hence, the hose galaxy's gravitational influence would have limited range.
GSwift7
4.2 / 5 (11) Aug 28, 2013
One problem with MoND is lensing, since there's no explanation of gravitational lensing with MoND. That's not the only problem though.

Merging galaxy clusters seem to have centers of mass that do not coincide with the visible mass, which does not fit MoND.

It's also not clear what the MoND violation of conservation of momentum would mean in terms of a finite speed of light and conservation of mass/energy.

Perhaps some form of MoGR would be more appropriate.
Q-Star
3.8 / 5 (10) Aug 28, 2013
One problem with MoND is lensing, since there's no explanation of gravitational lensing with MoND. That's not the only problem though.

Merging galaxy clusters seem to have centers of mass that do not coincide with the visible mass, which does not fit MoND.

It's also not clear what the MoND violation of conservation of momentum would mean in terms of a finite speed of light and conservation of mass/energy.

Perhaps some form of MoGR would be more appropriate.


Good point.

The problem I have with this paper is, if MOND works for this one dwarf galaxy, it should work with all dwarf galaxies, it doesn't . Physics are universal. If MOND works for dwarf galaxies, it should fit large elliptical and spirals even better, it doesn't.

I had thought by now the MOND proponents would have moved on, at least to the TeVeS attempts at modeling. There are some brilliant people working with MOND, I hope they don't end up like ya know who (both have the initials H.A.)
Q-Star
4.3 / 5 (11) Aug 28, 2013
I'm not saying it works or not - blah, blah, blah,,,,,,,


Zeph, Have ya bumped your head? Unable to afford your meds? Why so frantic and hysterical? Calm down boyo, ya'll make yourself ill.

Now, How can I find dwarf galaxies that don't fit the MOND model if they are don't fit. People don't publish a lot on failures,,,

But on the other hand, everyone publishes their successes, and I just can't find them. This is the only one that has made into the news.

Again, calm down, and I tell ya sincerely, I like getting the no votes from ya. I would worry is ya voted up.

Q-Star
4.1 / 5 (9) Aug 28, 2013
Are you mental case -


I'll let ya be the judge of that. I'm quite sure everyone would enjoy your take on that,,,, please use multiple posts and don't hold back,,,,

(This ought to be entertaining.)
rug
3.1 / 5 (9) Aug 28, 2013
Hey frank, check this out
http://scienceblo...ond-and/
Oh and this
http://blogs.disc...-thanks/
oh and here is some more
http://scienceblo...e-graph/

@Q-Star, Not to worry, I got your back! lol
dogbert
1 / 5 (11) Aug 28, 2013
"Most scientists are more comfortable with the dark matter interpretation," McGaugh said. "But we need to understand why MOND succeeds with these predictions. We don't even know how to make this prediction with dark matter."


That has always been the biggest flaw in the dark matter model -- the inability to predict.

In a comparison of the predictions calculated using MOND with observations of pairs of similar dwarfs, "the data appears to show MOND's prediction for the influence of the host, but it's fairly subtle," McGaugh said. MOND's predictions of the velocity dispersion were less subtle. These predictions were "really bang on," McGaugh said.


Yet a simple modification of our understanding of gravity is highly predictive of observations.
rug
2.3 / 5 (6) Aug 28, 2013
@dogbert - if you want to learn more about MoND and other odd and strange theories you should look at the links I posted above.
yyz
4.9 / 5 (7) Aug 28, 2013
"The finding bolsters the case McGaugh and Milgrom made for MOND's effectiveness in predicting properties in dwarf galaxies...."

But at the same time the article seems to imply that LCDM cannot account for dwarf galaxies, even in the Local Group, which a brief literature search shows is patently untrue:

http://arxiv.org/abs/1301.3131

http://arxiv.org/.../0701780

http://arxiv.org/.../0012051

The study of MOND may have some merit when it comes to the interpretation of some features of galaxies and clusters, but even most ardent (professional) supporters of MOND accept and acknowledge that DM is an essential component of any realistic model.
Gmr
2.6 / 5 (5) Aug 28, 2013

Yet a simple modification of our understanding of gravity is highly predictive of observations.


Observation. When it's singular you leave off the "s."
rug
1.9 / 5 (9) Aug 28, 2013
Well you know dogs can't spell.....
dogbert
1.4 / 5 (10) Aug 28, 2013
Gmr,
Observation. When it's singular you leave off the "s."


Correct and irrelevant since there were more than a single observation:

A modified law of gravity correctly predicted, in advance of the observations, the velocity dispersion—the average speed of stars within a galaxy relative to each other—in 10 dwarf satellite galaxies of the Milky Way's giant neighbor Andromeda.
IMP-9
5 / 5 (4) Aug 29, 2013

Correct and irrelevant since there were more than a single observation:


He's referring to the fact MOND does not describe large scale structure in the universe as seen in the work referenced by rug. Even at the level of clusters it requires missing mass to fit observation. Hence MOND does not fit all observations.
dogbert
1.7 / 5 (12) Aug 29, 2013
IMP-9,
MOND is predictive of a class of celestial objects -- dwarf galaxies.

Dark Matter is predictive of nothing at all. Kludges in general are not predictive.
rug
2.8 / 5 (6) Aug 29, 2013
Dark Matter is predictive of nothing at all. Kludges in general are not predictive.

Thats why it's only a stand in until it can be really figured out.

I'm sure there will be a theory to really explain the dark matter unknown but it does not appear to be MoND.
Q-Star
4 / 5 (9) Aug 29, 2013
Dark Matter is predictive of nothing at all. Kludges in general are not predictive.

Thats why it's only a stand in until it can be really figured out. .


Atoms, kluge,, oops we found them and figured out all kinds neat things about them.

Electrons, kluge,,, oops we found them too, just lucky I suppose.

Positrons, double kluge, it was a math kluge AND a particle kluge,,,,, well tickle me with a rusty nail,,,, somebody found it, and we use it daily in every major city.

Neutrons,now that was a silly kluge, they didn't believe there was such a real thing, but they needed it to make the maths work,,,,, wow, this is getting old, they found it.

Curved spacetime & GR? Math construct, kludge,,,, Took less than three years to experimentally confirm it. Passed every test thrown at is so far, & some really smart people tried to challenge it, the tests have gotten more rigorous, each year.

Point? If the right person calls something a kludge, it means ya are on the track.

dogbert
1.3 / 5 (12) Aug 30, 2013
rug,
Dark Matter is predictive of nothing at all. Kludges in general are not predictive.


Thats why it's only a stand in until it can be really figured out.


It is simply a kludge. Imaginary mass because our models of gravity do not match our observations of the universe. Generally, when a model fails to match reality, we modify the model but with gravity we seem stubbornly unwilling to entertain the notion that the model may be flawed. We insist that there must be imaginary mass to account for the discrepancy.

Sad.

Since no one has been able to find a single particle of dark matter despite massive effort, people are beginning to say that dark matter "is just a stand in". That is a cop out. If it were "just a stand in", we would not be looking for it.

Dark matter is simply a kludge to hide the fact that we will not consider that our models of gravity may be flawed. We insist that our observation is flawed because our models can't be flawed.

Not scientific.
yyz
5 / 5 (4) Aug 30, 2013
"Since no one has been able to find a single neutrino despite massive effort, people are beginning to say that neutrinos "are just a stand in". That is a cop out. If it were "just a stand in", we would not be looking for it."

"Neutrinos are simply a kludge to hide the fact that we will not consider that our models of the atom may be flawed. We insist that our observation is flawed because our models can't be flawed."

I guess that would be your position in 1930 dogbert. Stop wasting valuable time and money looking for neutrinos. They're a kludge. They don't exist.

Yeah, good thing we stopped looking for them, huh?
brt
2.3 / 5 (9) Aug 30, 2013
One problem with MoND is lensing, since there's no explanation of gravitational lensing with MoND. That's not the only problem though.

Merging galaxy clusters seem to have centers of mass that do not coincide with the visible mass, which does not fit MoND.

It's also not clear what the MoND violation of conservation of momentum would mean in terms of a finite speed of light and conservation of mass/energy.

Perhaps some form of MoGR would be more appropriate.


TeVeS is MoND married with Relativity. It supposedly solves the issues with MoND depending on how willing a person is to accept it. It looks pretty solid to me. I wish they would reference TeVeS instead of MoND. It's like referencing Newton's law of Gravity over Einstein's...so I guess it's appropriate in this article.
rug
1.8 / 5 (5) Aug 30, 2013
rug,
Since no one has been able to find a single particle of dark matter despite massive effort, people are beginning to say that dark matter "is just a stand in". That is a cop out. If it were "just a stand in", we would not be looking for it.
Dark matter is simply a kludge to hide the fact that we will not consider that our models of gravity may be flawed. We insist that our observation is flawed because our models can't be flawed.
Not scientific

There are some that think it might be an unknown form of matter. However, dark matter was introduced as a stand in until we could figure out what's wrong. A new type of matter would account for it. Thats not the only thing that is being looked into. That is very scientific.

If you understood what was going on you would have known this. Instead you make false claims and accusations. Either study before making uninformed post or shut the hell up.

http://en.wikiped...position
dogbert
1.6 / 5 (13) Aug 30, 2013
rug,

Almost daily, there are one or two articles on this site where there is the claim that they have found dark matter in gravitational lensing or other observations. The articles never mention place holders. They plainly declare dark matter.

Why not talk about gravitational anomalies? No, it is always dark matter.

When scientists treat fantasy as if it were reality, I will continue to point that out.
antialias_physorg
4 / 5 (5) Aug 30, 2013
When scientists treat fantasy as if it were reality, I will continue to point that out.

I guess you need to learn how to read scientific statements, then.

Dark matter is a concept/placeholder established by scientists. It's 'dark' because we can't see anything there and it's called 'matter' because it has a gravitational effect (and currently we know of only one thing that has that: matter).
That's it. Everything else is your interpretation. Scientists are notorious for naming stuff the simplest way (black hole, age of heavy bombardement, cosmic microwave background, ... )

You're harping on people having fantasies that they don't have. Only YOU think they have them. But that part you've made up all on your own.

You shoudln't be angry at people for your failures.
Modernmystic
1 / 5 (11) Aug 30, 2013
Dark matter is a concept/placeholder established by scientists. It's 'dark' because we can't see anything there


I thought it was because it is assumed to be "matter" which has been ascribed the property of not interacting electromagnetically with ordinary matter...

and it's called 'matter' because it has a gravitational effect (and currently we know of only one thing that has that: matter).


Then why are they looking for particles of the stuff if it might not be "matter" at all?

In short I believe some interpretive concepts have been insinuated by the scientists working on the problem. I would call it a tad intellectually dishonest to say otherwise and accuse someone else of a mental lapse for recognizing such.

rug
1.5 / 5 (8) Aug 30, 2013
Then why are they looking for particles of the stuff if it might not be "matter" at all?

Because it's one of the things out could be. It has been theorised to be matter that doesn't interact on the electromagnetic scale. (Which is what light is)

In short I believe some interpretive concepts have been insinuated by the scientists working on the problem. I would call it a tad intellectually dishonest to say otherwise and accuse someone else of a mental lapse for recognizing such.

It's not dishonest to come up with theories that describe what what is seen. The only dishonest thing about the whole topic is people saying it's dishonest.

I think you should read the article I linked a bit a go as well.
rug
1.8 / 5 (9) Aug 30, 2013
rug,

Almost daily, there are one or two articles on this site where there is the claim that they have found dark matter in gravitational lensing or other observations. The articles never mention place holders. They plainly declare dark matter.

Why not talk about gravitational anomalies? No, it is always dark matter.

When scientists treat fantasy as if it were reality, I will continue to point that out.


Why would they say anything but dark matter when that is exactly what dark matter is? Oh wait, that must be to complicated for you to understand. Let me make it simple for you.

Are you familiar with the equals sign? You know, that thing from 1st grade = that shows to things are the same? like 1=1

Good, now understand this.
Dark matter=unknown gravitational anomalies

When a theory works as well and general relativity has you don't just throw it out until something comes along that makes it obsolete. So far, nothing has done that. There are no better theories currently.
Modernmystic
1 / 5 (12) Aug 30, 2013
Because it's one of the things out could be. It has been theorised to be matter that doesn't interact on the electromagnetic scale. (Which is what light is)


Which is exactly what I said (about the electromagnetic part), and I never said we SHOULDN'T be looking for it as matter DID I??

Can you read anything without shoving opinions and attitudes on people?

It's not dishonest to come up with theories that describe what what is seen.


I never SAID that. What I said was it's dishonest to say that the scientists looking for dark matter AS "matter" most certainly HAVE assumed some properties and made some interpretations without necessarily having the hard data to do so. I'm not saying it's unreasonable to do so...GET IT?

I think you should read the article I linked a bit a go as well.


Tell you what, when you do some work on say 5th grade reading comprehension I'll look at that article mkay...

Q-Star
3.7 / 5 (6) Aug 30, 2013
Dark matter is a concept/placeholder established by scientists. It's 'dark' because we can't see anything there


I thought it was because it is assumed to be "matter" which has been ascribed the property of not interacting electromagnetically with ordinary matter...

and it's called 'matter' because it has a gravitational effect (and currently we know of only one thing that has that: matter).


Then why are they looking for particles of the stuff if it might not be "matter" at all?


I think he did misread your post. I'll try to help.

ALL observational and phenomenal evidence indicates it is matter. The "dark" only means we can not see it in our telescopes, it does not emit, reflect or absorb light. That is why so many people are concerned with finding it.. We're sure it's there, & since since we are sure it's there, we would like to know about it. Dark matter is not a place holder, it's an unfortunate term which was coined in a different era.
Q-Star
3.7 / 5 (6) Aug 30, 2013
@ Modernmystic,

If ya would like, I will try to help ya with what the "mainstream" views on dark matter are, why we are sure,,, what we think we know well,,, what we think we know sorta well,,, and what we just plain don't know. And why we think it.

But I would rather not engage in philosophy or ponderings, I'm most comfortable with science based on 1st Principles. So maybe we can begin over, eh?
rug
2 / 5 (4) Aug 30, 2013
Then why are they looking for particles of the stuff if it might not be "matter" at all?
Because it's one of the things out could be. It has been theorised to be matter that doesn't interact on the electromagnetic scale. (Which is what light is)

It's a simple answer to your question. What is so wrong with that? or did you not want an answer?
rug
2.3 / 5 (6) Aug 30, 2013
Yes, I did miss read that one portion of your post. I apologize. The article I linked to is just the wiki page for Dark Matter. It has a lot of good info in there. When you look at the history section is shows the process that has been taken to even get the point of looking for particles of dark matter.
Q-Star
4 / 5 (8) Aug 30, 2013
Technically the dark matter is really the matter if we consider, http://www.newsci...ime.html a repulsion up to certain distance. Also, due the weak curvature of space-time inside of dark matter, it doesn't exhibit charge and it interacts only magnetically.


Hey Zeph, there ya are. Good post,,,

So now we should modify our AWT a bit to account for the dark dense vacuum of spacetime curvature?

Can the electron ducks and the water walking photon spiders surfing the waves rippling in a dense dark vacuum navigate independantly? Or do they require some light dense vacuous matter to see where they are going?

Would ya post one of those pictures so I can get a handle on it?
rug
1.6 / 5 (7) Aug 30, 2013
Hi Frank, your LQG has one major issue.
"LQG hasn't yet even reproduced the predictions made by general relativity."
http://en.wikiped...proaches
antialias_physorg
4.2 / 5 (5) Aug 30, 2013
Then why are they looking for particles of the stuff if it might not be "matter" at all?

Because you test the best theory you have first. We really don't know if it is matter (certainly looks like it, though, as it seems to clump up). If they don't find any 'dark matter' particles then scientists will move on to the next possibility and test that. All other theories do posit a lot of free variables (i.e. they're not very testable at the moment).

Even NOT finding any particles can narrow down the search.

In short I believe some interpretive concepts have been insinuated by the scientists

Nope. The insinuation is all in your head.

It's actually not your fault, because scientists talk and write differently from journalists. You have to really learn to read scientific papers in order to get that. Anything that is not EXPRESSLY in a scientists's statement isn't there. It's that simple. Journalisms is different. It plays with (and on) your preconceptions.
Modernmystic
1 / 5 (5) Aug 30, 2013
Because you test the best theory you have first. We really don't know if it is matter (certainly looks like it, though, as it seems to clump up).


That and they're "assuming" it's matter, ie. insinuating a property they have no direct evidence for despite the good correlative reasons for doing so. Otherwise why look for it AS matter? Yes I understand it may not be a solid assumption, it may be that SOME of them are looking for it as matter just to rule out matter. Which was my point. Accusing someone of some kind of intellectual failure for calling that spade a spade is dishonest or ignorant.
It's actually not your fault, because scientists talk and write differently from journalists. You have to really learn to read scientific papers in order to get that. Anything that is not EXPRESSLY in a scientists's statement isn't there. It's that simple. Journalisms is different. It plays with (and on) your preconceptions.


Oh, the irony.........
Q-Star
3.3 / 5 (10) Aug 30, 2013
@ Anti-... not to quibble over nit picky stuff, but some of those we are engaging with require the utmost care when explaining it to them.

We really don't know if it is matter (certainly looks like it, though, as it seems to clump up).


Unless there are some physics going on that are completely unconnected with any science anyone has ever done,,it is matter,. We are as sure of it being matter as can be until we can hold it in our hands and put some in a jar. What we don't know is the complete nature of this matter. It must have mass and interact gravitationally so it's matter. It can be any of variety of things, but all those things must be matter.

The only way it is not matter, is if our fundamental forces work differently from one place in the universe to another,,,, and that concept is waaaaay out there scientifically meaning from the fringe towards the crank.
rug
1.9 / 5 (8) Aug 30, 2013
That and they're "assuming" it's matter, ie. insinuating a property they have no direct evidence for despite the good correlative reasons for doing so

Well, that is exactly what a theory is. Come up with an idea of what's going on and test it. Everything in science is a theory so there really is no need to point it out. Anyone that is scientifically literate knows all of this from the get go.

Accusing someone of some kind of intellectual failure for calling that spade a spade is dishonest or ignorant.

True, so what's the point?
Q-Star
3.5 / 5 (8) Aug 30, 2013
Because you test the best theory you have first. We really don't know if it is matter (certainly looks like it, though, as it seems to clump up).


That and they're "assuming" it's matter, ie. insinuating a property they have no direct evidence for despite the good correlative reasons for doing so.


The only direct evidence is why the assuming of matter. It's not just "a wild random" guess or "whimsy". There is tons of direct evidence. The is NO evidence direct or otherwise that it could be anything else. Zip, Zero, Nada......

Now if ya want to argue the quality of that evidence, I offered to help ya sort through so ya understand why the "mainstream" thinks what they do.

But if ya just want a priori to say there is no evidence and it's ALL unfounded assumptions, then ya really don't want to understand, ya are just determined that it is wrong and a reason it is wrong is not required.
antialias_physorg
4.2 / 5 (6) Aug 30, 2013
Unless there are some physics going on that are completely unconnected with any science anyone has ever done,,it is matter,

Agreed. And I think the likelyhood that this turns out to be some form of matter is huge (that's why we must test that theory first).
Nevertheless we haven't found any dark matter particles, yet. So at this stage I wouldn't say that it's an open-and-shut case. Some new physics would be cool (always crossing my finger for that - as I'm sure all scientists are). So I'll just wait and see what the detectors currently being set up will tell us.
Q-Star
3 / 5 (10) Aug 30, 2013
Some new physics would be cool (always crossing my finger for that - as I'm sure all scientists are). So I'll just wait and see what the detectors currently being set up will tell us.


That's what the cranks, crackpots and dreamers just can't understand. Tearing down the old science replacing with new is what science is. Scientists don't defend their science selfishly to maintain the comfortable safe place they are in. Every scientist would give his eyeteeth to cast Einstein down. But they work on with a lot more than their hearts desire,,,, whereas the internet cafe want to circumvent the 1st Principles, the work to know the field, or endure getting over failures.

They want to go straight from kindergarten to bringing the world the "new paradigm" without the trouble of silly things as fundamental science, those annoying maths, and discipline. Otherwise they would realize someone else already tried that particular brilliant idea and found that it didn't/couldn't work.
rug
1.6 / 5 (7) Aug 30, 2013
I don't know, it has worked in the past. Newton, Einstein, and Galileo, just to name a few, came on the science scene with a bang and went into history as change just about everything.

Granted, they are few and far between and none of the trolls around here have any clue.
Q-Star
3.9 / 5 (7) Aug 30, 2013
I don't know, it has worked in the past. Newton, Einstein, and Galileo, just to name a few, came on the science scene with a bang and went into history as change just about everything.


But ya missed my point,,,, all those guys worked at their science, they learned required foundation, they were willing to throw out a 100 ideas while TESTING for the 1 that worked. They practiced science as opposed to reading a crank paper & proclaim the "new paradigm" without seeing if it would even work.

It's why I find it ridiculous when they point to an "authority" as if the very name is all that is important. When point out the name without using the science it tickles me.

Einstein had more wrong ideas than he did right, as did Galileo, Newton, Bohr, Feynman, & EVERYONE else from top to bottom. The name is not science, they are remembered because they got ONE or TWO big ideas right. Their failures are all part of history,, it's just not as big history as their monumental successes.
rug
1.6 / 5 (7) Aug 30, 2013
No, I got your point and agree 100% I was just giving you a hard time. lol
rug
1.6 / 5 (7) Aug 30, 2013
You're not in position to define what the science is at public. I do perceive it rather like somewhat cyclical evolution based on emergence of facts.

And just how do you suppose these facts are come by? Dare I say it? "Tearing down the old science replacing with new" when something that makes more sense and fits the evidence better.

The detectors are running twenty years already and they found nothing.

Um, thats not even close to true. http://en.wikiped...Findings

BTW If Einstein would just sit down and wait for detectors, he could never predict anything new.

You do realize most of his work was done while he was sitting down right? Not everyone needs to come up with new things. People are needed to test the theories, and some people (like some of us here) like to read and learn. Be dazzled by the wonders of the universe. With in factual science.
Q-Star
4 / 5 (8) Aug 30, 2013
You're not in position to define what the science is at public. I do perceive it rather like somewhat cyclical evolution based on emergence of facts.


Sorry, Zeph, but I have to know,,,,, what does "somewhat cyclical evolution based on emergence of facts" mean? It has a nice ring to it, so I know it must mean something profound, would help me out here?

The detectors are running twenty years already and they found nothing.


No Zephyr, the aether detectors have been running 140 years already and they found nothing.

BTW If Einstein would just sit down and wait for detectors, he could never predict anything new.


He got tire of waiting on the right aether detectors went on to predict something new,,,, aren't glad he did?
antialias_physorg
3.7 / 5 (6) Aug 30, 2013
Newton, Einstein, and Galileo, just to name a few,

The fun thing is, though, if you read up on the history of these (at least Galilei and Einstein): They developed their revolutionary stuff not out of thin air. A lot of it was based on the stuff that came before (Einstein actually 'only' added the idea about the speed of light being constant and everything fell into place from that from known laws).
It's a combination of a brilliant idea with a deep understanding of the physics of the time and the hard learning required to develop the mental tools to be able to work out where that leads.
It's also the integrity of trying out a lot of things and being able to see which ones don't work (which even for their likes is more than 90%)

That's what the armchair cranks can't do. Since they lack the understanding/abilities to check their ideas they never can understand whether their ideas are good or not. So they remain caught forever thinking that their brainfarts are brilliant.
Q-Star
3.9 / 5 (7) Aug 30, 2013
what does "somewhat cyclical evolution based on emergence of facts" mean
Well, the people collect facts, when their density exceeds critical level, the density gradients inside of these facts are recognized and postulated like the theory. The another facts fill gap between the theories until they form another level of continuum and new theories are developed, and so on. We can often observe dual oscillations: for example the people considered light the waves, then particles, after then wave again and gradually converged to wave-particle duality. I.e. the people ofter return to older ideas, when the existing theories aren't fitting well the newly revealed facts anymore.


Aaah, the AWT, why didn't ya just say that? We're all up to speed on the AWT.
Q-Star
3.9 / 5 (7) Aug 30, 2013
We have multiple field-like theories of dark matter too, but the MOND, TeVeS and STVG are just few of them. Each theory describes some particular aspect of dark matter better than others, but none of them represents sufficiently complete theory of dark matter.


But only one field-like theory fits all, the AWT. Those others, MOND, TeVeS and STVG and a few more have the baggage of not being self-consistent. Unlike the AWT of course.
rug
1.6 / 5 (7) Aug 31, 2013
The dark matter violates the weak equivalence principle in four dimensions

No it doesn't
so you really may not want to develop dark matter theories with using of the general relativity based on equivalence principle.

Why not? It's the best working theory so far. General relativity has made many predictions that were later found.
The Newtonian law and/or mass-energy equivalence are another potential sources of inconsistence of general relativity.

No it's not.
This doesn't mean, they cannot provide testable quantitative predictions in the scope of their validity.

Because they have.
But the operational scope of these formal theories is usually low: they fit cold dark matter only and they usually fit just some particular aspect of dark matter behavior, for which they were designed.

So what is your point?

Once again you put walls of text trying to refute what you do not understand.
Q-Star
3.5 / 5 (8) Aug 31, 2013
so you really may not want to develop dark matter theories with using of the general relativity based on equivalence principle.


Dark matter theories (the mainstream theories, not crank) aren't founded on general relativity. The are based first on Newtonian mechanics: The dark matter is 1) not moving at relativistic velocities &,, 2) is not sufficiently concentrated to require application of the mass-energy equivalence principle of general or special relativity.

But the operational scope of these formal theories is usually low: they fit cold dark matter only and they usually fit just some particular aspect of dark matter behavior, for which they were designed.


They fit cold dark matter only, & the only particular aspect they operate on is it has mass. It's cold & it's dark are two words which in this case mean the exact same thing.

Hot dark matter is not dark, it is a contradiction, we've been able to "see" neutrinos for a while now. There is not enough of them.
vidyunmaya
1 / 5 (11) Sep 01, 2013
Sub: Cosmic function within the Universe
In a Three-tier Cosmic Pot Universe, Super-imposition of the Visible-Invisible Matrix over Space based observations help a clear and better mode for Interpreations.
see papers through Carnegie-2003 and stsci-symposium-2003. Change to new concepts -Basic approach needed.
vidyardhicosmology [dot]blogspot [dot]in/2011/10/light-flow-interaction-plasma-vision [dot]html
lengould100
1.2 / 5 (10) Sep 01, 2013
Qstar claims:

Tearing down the old science replacing with new is what science is. Scientists don't defend their science selfishly to maintain the comfortable safe place they are in.


Not QUITE true, in fact there are several examples in science where a new and more correct interpretation of facts had to wait for a generational turnover of entrenched scientists committed to the then-current accepted paradigm. Plate tectonics is one obvious example. which springs to mind.
lengould100
1 / 5 (8) Sep 01, 2013
From John Moffat's presentation on STVG, see http://www.johnwm...2010.pdf

The STVG theory has an extra degree of freedom, a vector field called a "phion" ( φµ ) field whose curl is a skew field that couples to matter ("fifth force"). The gravitational field is described by a symmetric Einstein metric tensor. The fifth force charge is proportional to mass Q5 = κ M.


•A fitting routine has been applied to fit a large number of galaxy rotation curves (101 galaxies), using photometric data (58 galaxies) and a core model (43 galaxies) (J. R. Brownstein and JWM, 2005). The fits to the data are remarkably good and for the photometric data only one parameter, the mass-to-light ratio M/L, is used for the fitting once two parameters α and λ are universally fixed for galaxies and dwarf galaxies.
•A large sample of X-ray mass profile cluster data (106 clusters) has also been well fitted (J. R. Brownstein and JWM, 2005; JWM and V. T. Toth, 2007,2008;

lengould100
1 / 5 (7) Sep 01, 2013
cont'd

•The rotational velocity curves become the Kepler-Newtonian curves at large distances from the galaxies (satellites).
•The Tully-Fisher law is satisfied by MOG:
• For every feature in the surface brightness distribution, MOG produces a corresponding feature in the predicted rotation curve (matching the observed rotation curve).


IMHO, this is the strongest contender to come out accepted in the long run, including "dark matter".
Raygunner
1 / 5 (9) Sep 02, 2013
rug,

Dark matter=unknown gravitational anomalies

should be:

Don't know=unknown gravitational anomalies
antialias_physorg
3.7 / 5 (3) Sep 02, 2013
Dark matter=unknown gravitational anomalies

should be:

Don't know=unknown gravitational anomalies

You need a label so that you know when two people in different papers are talking about the same thing. "Don't know" is not a good label.

If you have a label than you can slowly add properties (as detected/inferred) to it and build a complete picture.
Q-Star
3.9 / 5 (7) Sep 02, 2013
Dark matter=unknown gravitational anomalies

should be:

Don't know=unknown gravitational anomalies

You need a label so that you know when two people in different papers are talking about the same thing. "Don't know" is not a good label.

If you have a label than you can slowly add properties (as detected/inferred) to it and build a complete picture.


Very good point. And "anomalies" is the word used by people who aren't actually working or even studying in the area. It happens the same way, every time, when ever ya observe it, by every means that can infer it. It's self-consistent, so it is not as "anomaly".
Q-Star
3.5 / 5 (8) Sep 02, 2013
Hot dark matter is not dark, it is a contradiction
http://en.wikipedia.org/wiki/Hot_dark_matter. Why not to read even basic Wikipedia article about it before posting? What's wrong with you? Do you suffer with compulsive lying syndrome or what? At the moment, when you open your mouth about it, it's immediately apparent, you didn't learn absolutely anything about subject - you're just inventing silly stuffs about it at public.


Thanks Zeph, now I know I'm on the right track, not that I doubted it, but it is nice that confirmed if for me.
Q-Star
3.5 / 5 (8) Sep 02, 2013
Dark matter theories (the mainstream theories, not crank) aren't founded on general relativity. The are based first on Newtonian mechanics

You're dumb and therefore wrong in every sentence of yours. General relativity itself is based on Newton's gravitational law, so if you modify the Newtonian law, you'll modify the general relativity too. This is how the predictions of http://arxiv.org/abs/0709.2561 are working. The Newtonian mechanics doesn't predict the gravitational lens, the relativity does - sodoes the MOND too. All other dark matter theories (STVG, TeVeS, MOG, etc.) alre already based on corrections of general relativity and they indeed predict gravitational lensing too.


Once more I must thank ya for giving me a greater degree of confidence in how I was assimilating the science. Ya prove to me that I must be on the right track. Zephyr, shouldn't ya be boning up on your Lodge papers and preparing to dazzle the world with the Modified AWT?
Fleetfoot
5 / 5 (4) Sep 06, 2013
The fun thing is, though, if you read up on the history of these (at least Galilei and Einstein): They developed their revolutionary stuff not out of thin air. A lot of it was based on the stuff that came before (Einstein actually 'only' added the idea about the speed of light being constant and everything fell into place from that from known laws).


Not even that, he took the postulate that the speed of light is anisotropic from Maxwell's Equations which of course were derived empirically by many others. His leap was to recognise that there was a conflict between those experiments and Newton's philosophical assumption of "absolute time" and discarding the right one. It is a prime example of the scientific method in action.
Fleetfoot
5 / 5 (4) Sep 06, 2013
General relativity itself is based on Newton's gravitational law ..


Still trotting out this erroneous statement Zephyr? You should have learned it is untrue by now.

The Newtonian mechanics doesn't predict the gravitational lens, the relativity does - so does the MOND too.


Newtonian gravity does predict lensing but at half the observed value. Above some arbitrary acceleration, MOND is asymptotic to Newtonian gravity so it gets it wrong by the same amount. That was known from when it was first published, it was intended to be a starting point only aiming towards something like TeVeS, STVG or BSTV. None of these quite fits the data either and all still require dark matter in addition to the altered gravitational equations.
Fleetfoot
5 / 5 (4) Sep 06, 2013
Because you test the best theory you have first. We really don't know if it is matter (certainly looks like it, though, as it seems to clump up).


That and they're "assuming" it's matter, ie. insinuating a property they have no direct evidence for despite the good correlative reasons for doing so. Otherwise why look for it AS matter? Yes I understand it may not be a solid assumption, it may be that SOME of them are looking for it as matter just to rule out matter.


Part of the problem is that there isn't a clear definition of what constitutes "matter". Dark matter must have energy to create a gravitational effect. If it were massless, it would move at the speed of light so couldn't "clump" as antialias said. "Particles which have non-zero rest mass" is one reasonable definition for "matter" so the term is appropriate based on the limited information we have at present.

http://en.wikiped...i/Matter
ralph638s
1 / 5 (5) Sep 07, 2013
How does MOND compare with Notalle's (not to be confused with Natello) theory of Scale Relativity?
ralph638s
1 / 5 (5) Sep 07, 2013
oops, I meant Nottale (still not to be confused with Natello)

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