>dark matter: old and busted
>Milgromian dynamics: new and hot
>Dark matter: Our review suggests it's time to ditch it in favor of a new theory of gravity
https://phys.org/news/2022-07-dark-ditch-favor-theory-gravity.html
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>However, in a recent review my colleagues and I suggest that observations across a vast range of scales are much better explained in an alternative theory of gravity proposed by Israeli physicist Mordehai Milgrom in 1982 called Milgromian dynamics or Mond—requiring no invisible matter.
Now that somebody has said it we just have to wait for the old blowhards to die. An exciting moment for science, to throw away old trash and make new trash.
Well it's hard to make any real progress in this area because even the brightest minds can not agree on what gravity actually is let alone how it functions.
Miles Mathis already solved all of this 10-20 years ago
>enters thread
>makes ridiculous claim
>refuses to elaborate
>leaves thread
Zoomer moment.
>phys.org
>reads like a IQfy thread
This is is wild
>jews
>gravity
>high school level English
Damn you're right, thats bizarre
The images speak for themselves. More and more real scientists are speaking out. Your time of paycheck stealing is at its end.
and this is MOND
>Offset between X-ray and lensing in Bullet Cluster
>Works well
Lel. It works well by adding dark matter.
>Mainly due to this offset, the Bullet Cluster is quite
difficult to reproduce in MOND using only its directly de-tected baryonic matter (Knebe et al. 2009). However, the Bullet Cluster can be reconciled with MOND using extra collisionless matter
This is the state of MOND "research" today. If it's broke, add dark matter but continue to claim what you're doing is superior.
>Dark matter: Our review suggests it's time to ditch it in favor of a new theory of gravity
I can't believe the wildly inaccurate "theories" have last as long as they have.
This image fails to take into account the fact that we can see the accretion disks around black holes, which would have to be invisible
>star travelling at 0.51C away from Earth
>Earth traveling at 0.51C away from star
Based on current theories of relativity then from the perspective on Earth they would be moving apart at like ~0.8C since time would be moving slower on Earth than at whatever point the person making this meme is standing. At least I'm fairly confident that's what the problem is, but I'm also tired and can't be arsed to verify/explain how that absurdly counterintuitive thing works. Just google the second postulate of relativity.
an alternative theory of gravity doesn't explain why dark matter is clumped in some areas and not in others, if gravity just worked that way then the phenomenon should be uniform, but it's not
This here; there are a handful of dwarf galaxies that do not have the large scale discrepancies in their motions, and do behave as standard gravity models predict they would from their visible matter. They are sometimes called "dark matter deficient galaxies", as the dark matter hypothesis can explain these galaxies behavior by some large scale event in the past separating the dark matter from the visible matter. Any modified gravity theory will have to have some explanation as to why these galaxies behave so differently from other galaxies with similar amounts of visible matter. As far as I can tell, this theory here does not address those galaxies.
Dark matter doesnt exist
Yes that's what the article is about.
dark matter is just the name given to consistent observational evidence that *something* is there
you can't just say "hurr it doesn't exist" while ignoring that evidence, because clearly something is causing those observations
They dont have any evidence. It's just one explanation to make the old model of gravity work.
A small tweak to the newtons gravity makes them work for 99% of the cases. Dark matter deficient galaxies still need a proper explanation in MOND but it's not a big deal.
no, there's definitely evidence, visible matter is behaving as if something heavy is in some areas and not in others
because it can't be seen directly apart from that, it's called dark matter
tweaks to the theory of gravity cannot account for that non-uniform distribution of dark matter
And the sun was behaving as if it revolves around the earth one point. Simpler explanation always win in the end.
I suggest you read the article in OP and look at the images
>tweaks to the theory of gravity cannot account for that non-uniform distribution of dark matter
And there are things that MOND can explain that cannot be explained by dark matter. RTFA
a simpler explanation is welcome to win, but it actually has to be an explanation that accounts for observation
this one doesn't
>explanation that accounts for observation
And dark matter doesn't?
dark matter is not an explanation of anything, it's the observation
Then what is the explanation for
>visible matter is behaving as if something heavy is in some areas and not in others
i don't know, but i do know it's unlikely to be a modified theory of gravity, since that doesn't mesh with the thing you greentexted
i don't know why dark energy and dark matter make brainlets seethe so much, they're just phrases used to refer to things that have been observed but have not been explained
For one they're wasting real money trying to build detectors for finding dark matter that can be easily explained by alternative models
if it's so easy, then why hasn't anyone done it yet
They just did.
nope, this has been done many times before but they're just pretending to be moronic and ignoring well-documented data
there is no explanation for why dark matter is clumped there
>there is no explanation for why dark matter is clumped there
True. Camp A has no explanation for anything. Camp B has an explanation for 99% of things. To me it looks like camp B is doing more useful work.
whatever work is being done, nobody has debunked dark matter yet
but it can't
Can't what?
it can't be replaced by an arbitrary modification to physics
> small tweak to the newtons gravity makes them work for 99% of the cases.
No it doesn't. That is why all current MoND theories fail hard.
There are at least 6 different types of unique astronomical observations that are currently unexplained. Each of the alternative gravity theories can explain two at best but breakdown on the rest. The dark matter particle(s) hypothesis explains them all, and the new observations made, in a single simple theory. *That* is why it's the current best guess.
>There are at least 6 different types of unique astronomical observations that are currently unexplained
So they're lying in this image when they left the bottom row blank?
Lying and/or misleading. Most of the effects are irrelevant and don't even require DM to explain. The Einstein Ring one made me chuckle.
The bottom row isn't the problem, you've been duped by this cheap slight of hand. Look at the right column, "Auxiliary assumptions
allow theory to fit any plausible data". THey are admitting that their model requires modifications to do these things, and that the freedom in those modifications means you can do fricking anything. If it's consistent with any data in what sense is it an "excellent agreement"? That's fricking stupid. If something is consistent with anything then there are no degrees of agreement. And note the modifications they're talking about are adding new invisible fields and particles to MOND. In this one cell they have all the cosmological tests they have considered (ignoring most cosmologyical data). And they clearly admit MOND doesn't work on cosmological scales and needs massive new kludges.
But the standard model also has that rightmost column with more things in it
None of those things require adding new types of matter or fields. They are galaxy scale problems. Such issues can be solved by making changes to the recipes for galaxy evolution, which is still very uncertain anyway. And note, it's an entirely biased list of "tests" complied and ranked by two MOND researches.
As I explained the fact that there are things different levels of agreement in this column is proof the paper is fricking stupid. If something is really consistent with anything then there is no good or bad agreement.
Im not sure I can trust a mexican physicist with a name that sounds like a type of allergy medicine
The "review" is written by two prolific MOND researchers. Of course they continue to claim that MOND is better. Their matrix is trash. The list of "tests" they chose is just a summary of their favourite MOND papers and some arbitrary labels. Note that almost all of them are about galaxies, only 4 cover cosmological scales. That's absurd. Most cosmological data is ignored.
Also note that MOND is not even a real cosmology because it's classical, it's not compatible with general relativity. To build a relativistic MOND there are many choices to be made, by adding new invisible fields. Many versions have been ruled out.
Dark energy is a separate scam but that can be explained by variable gravity
It's a scam because it can be replaced by a different arbitrary modification to physics. Wow, that's so much simpler. You've turned replaced one modification, with another different modification.
>with another different modification
That makes falsifiable claims and offeres better predicitons.
People ITT are demanding 100% rigour from MOND where as their own model has magical elements that give no explanation at all.
To me it likes people are seething at MOND more than peoppe seething at dark matter
>That makes falsifiable claims and offeres better predicitons.
Please post such a model.
> 100% rigour from MOND where as their own model has magical elements that give no explanation at all.
Where does the MOND modification come from physically? There is no explanation, it's just a kludge. It was made up based on observations of galaxies, it's an empirical kludge. Even now there is no accepted explanation for the origin of the MOND acceleration scale.
Where does the gravitational constant come from physically? That was also a kludge. Again this is just repeating the same BS demanding 100% rigour from MOND while giving a free pass to existing models.
>Please post such a model.
>Imagine that we know the distribution of visible mass in a galaxy but do not yet know its rotation speed. In the standard cosmological model, it would only be possible to say with some confidence that the rotation speed will come out between 100km/s and 300km/s on the outskirts. Mond makes a more definite prediction that the rotation speed must be in the range 180–190km/s.
>If observations later reveal a rotation speed of 188km/s, then this is consistent with both theories—but clearly, Mond is preferred.
So MOND made better predicitons than dark matter
>Where does the gravitational constant come from physically? That was also a kludge.
It's still a kludge, but not on the same level. The only difference is the Newton derived the form of his universal gravitation from geometric arguments. That left him with a missing constant. In the case of MOND there was no prescription for what form the modification should take, there was no geometric argument or anything else. It was purely empirical. You have serious freedom when you can add free functions, not just free parameters.
>Please post such a model.
MOND does not explain dark energy. It's not a real cosmology.
>So MOND made better predicitons than dark matter
Unless of course you go beyond looking at galaxies like stamp collecting and look at wider scales.
Does MOND explain galaxy clusters? No, there is a mass deficit in MOND which proponents argue can be solved by adding missed matter (dark matter to you and me).
Or what about cosmology and the expanding universe, does MOND do better predictions? Again, nope. MOND is classical and not compatible with relativity so you can't even make real MOND predictions for most cosmological data. But people try anyway, and it gets things hilariously wrong, such as the statistics of the cosmic microwave background:
. But proponents just ignore this. MOND isn't relativistic so these aren't really predictions. Clearly a relativistic MOND will solve all of their problems, but that is just an empty fantasy. So no, MOND does not make better predictions. It can't even make predictions for anything on cosmological scales.
>Imagine that we know the distribution of visible mass in a galaxy but do not yet know its rotation speed. In the standard cosmological model, it would only be possible to say with some confidence that the rotation speed will come out between 100km/s and 300km/s on the outskirts. Mond makes a more definite prediction that the rotation speed must be in the range 180–190km/s.
Also this quote is false. This isn't a unique prediction, it's the Tully-Fisher relation. TF is an empirical relation in galaxy rotations that was found before MOND. The TF is one of the things that when into MOND, MOND is essentially a fit of this and other things. But current simulations with dark matter also reproduce the TF relation. So you can also predict the rotation velocity. The other thing you can do with dark matter models is match simulated halos to real galaxies by their visible mass. This works pretty well, from the total mass one can predict how closely this galaxy will cluster to other galaxies. You cannot do that in MOND.
Rebranding empirical scaling relations as "MOND predictions" is incredible cope.