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Fascinating. So this MOND theory works in this case. If I understand correctly, scientists still prefer the dark matter theory because it applies in more cases

Fascinating. So this MOND theory works in this case. If I understand correctly, scientists still prefer the dark matter theory because it applies in more cases at galactic scale, and this is just one occurrence of the MOND theory working fine?

rocqua 3y ago
We have found galaxies with differing amounts of dark matter (as measurer by rotational speed) and have confirmed these measurements with gravitational lensing being more or less effective.
bena 3y ago
I think dark matter is more appealing to them because the first person to discover a dark matter object is going to get something named after them.
- Ar-Curunir 3y ago
  First, most modern research in physics (especially experimental physics) have a ton of coauthors; we’re well past the stage of things being named for a single person. Second, what makes you think there isn’t great fame in disproving dark matter?
- mr_mitm 3y ago
  That doesn't make any sense at all unless they simultaneously believe that DM is actually the right answer.
  - bena 3y ago
    I’m sorry, I can see where I was ambiguous. I meant I can see why dark matter is appealing to more researchers in general and why MOND is in the minority. If dark matter is right, we can find it. If MOND is right, we’ve just been doing incomplete math this whole time. One of those is way more exciting.
    - kadoban 3y ago
      The last person who figured out we were doing incomplete math is the single most famous scientist in the history of the world. Being the next one isn't more exciting than getting some particle named after yourself?
      - cdelsolar 3y ago
        Yeah I interpreted that person’s post as saying “we’ve been doing incomplete math this whole time” is way more exciting, which I completely agree with.
    - cryptonector 3y ago
      The real issue is that you need a lot of money to test DM for real, but not so much to test MOND.
mr_mitm 3y ago
They prefer it because it fits the data best. The biggest piece of evidence for DM is the BAO patterns in the CMB. Forget all the other numerous mountains of evidence, that is the biggest one. MOND has no good explanation for this without introducing something that's effectively DM.
- beautifulfreak 3y ago
  Perhaps you meant... DM = Dark Matter, BAO = Baryon Acoustic Oscillations, CMB = Cosmic Background Radiation, MOND = Modified Newtonian Dynamics
- moffkalast 3y ago
  To put some sources to that unsubstantiated "data", it's about the Bullet Cluster specifically. https://en.wikipedia.org/wiki/Bullet_Cluster#Significance_to_dark_matter https://en.wikipedia.org/wiki/Bullet_Cluster#Significance_to...
- throwawaymaths 3y ago
  DM can't explain renzo's rule, or the tully-fisher relationship, or why the milky way has a keplerian return (efe from the magellanic clouds), or why elliptical and lenticular galaxies don't seem to have dark matter. All these are explainable by MOND. MOND also predicted early galaxies, and a group seeking to disprove MOND by disproving EFE changed their mind because they found evidence of EFE. > it fits the data best. It's easy to fit the data when you can conjure a parameter to explain anything. What if I told you that GR is wrong and there's a ball of dark matter orbiting the sun that distorts Mercury's orbit. You wouldn't be able to prove me wrong.
  - mr_mitm 3y ago
    I wouldn't have to prove you wrong. If your stance is that Mercury's perihelion shift is explained by DM, then I'll counter that GR explains that, gravitational lensing, gravitational waves, black holes, the CMB, the helium abundance, and then some. By Occam's razor, GR would be the preferable theory. The claim that DM requires conjuring up parameters is completely baseless. There are one or two parameters (besides a handful other parameters from LambdaCDM) that determine the statistics of the DM distribution, and observations match well with simulations based on those parameters. There are small deviations called the dwarf galaxy problem and no one is inventing parameters to explain those, so what are you talking about?

rocqua 3y ago

We have found galaxies with differing amounts of dark matter (as measurer by rotational speed) and have confirmed these measurements with gravitational lensing being more or less effective.

bena 3y ago

I think dark matter is more appealing to them because the first person to discover a dark matter object is going to get something named after them.

Ar-Curunir 3y ago
First, most modern research in physics (especially experimental physics) have a ton of coauthors; we’re well past the stage of things being named for a single person. Second, what makes you think there isn’t great fame in disproving dark matter?
mr_mitm 3y ago
That doesn't make any sense at all unless they simultaneously believe that DM is actually the right answer.
- bena 3y ago
  I’m sorry, I can see where I was ambiguous. I meant I can see why dark matter is appealing to more researchers in general and why MOND is in the minority. If dark matter is right, we can find it. If MOND is right, we’ve just been doing incomplete math this whole time. One of those is way more exciting.
  - kadoban 3y ago
    The last person who figured out we were doing incomplete math is the single most famous scientist in the history of the world. Being the next one isn't more exciting than getting some particle named after yourself?
    - cdelsolar 3y ago
      Yeah I interpreted that person’s post as saying “we’ve been doing incomplete math this whole time” is way more exciting, which I completely agree with.
  - cryptonector 3y ago
    The real issue is that you need a lot of money to test DM for real, but not so much to test MOND.

mr_mitm 3y ago

They prefer it because it fits the data best. The biggest piece of evidence for DM is the BAO patterns in the CMB. Forget all the other numerous mountains of evidence, that is the biggest one. MOND has no good explanation for this without introducing something that's effectively DM.

beautifulfreak 3y ago
Perhaps you meant... DM = Dark Matter, BAO = Baryon Acoustic Oscillations, CMB = Cosmic Background Radiation, MOND = Modified Newtonian Dynamics
moffkalast 3y ago
To put some sources to that unsubstantiated "data", it's about the Bullet Cluster specifically. https://en.wikipedia.org/wiki/Bullet_Cluster#Significance_to_dark_matter https://en.wikipedia.org/wiki/Bullet_Cluster#Significance_to...
throwawaymaths 3y ago
DM can't explain renzo's rule, or the tully-fisher relationship, or why the milky way has a keplerian return (efe from the magellanic clouds), or why elliptical and lenticular galaxies don't seem to have dark matter. All these are explainable by MOND. MOND also predicted early galaxies, and a group seeking to disprove MOND by disproving EFE changed their mind because they found evidence of EFE. > it fits the data best. It's easy to fit the data when you can conjure a parameter to explain anything. What if I told you that GR is wrong and there's a ball of dark matter orbiting the sun that distorts Mercury's orbit. You wouldn't be able to prove me wrong.
- mr_mitm 3y ago
  I wouldn't have to prove you wrong. If your stance is that Mercury's perihelion shift is explained by DM, then I'll counter that GR explains that, gravitational lensing, gravitational waves, black holes, the CMB, the helium abundance, and then some. By Occam's razor, GR would be the preferable theory. The claim that DM requires conjuring up parameters is completely baseless. There are one or two parameters (besides a handful other parameters from LambdaCDM) that determine the statistics of the DM distribution, and observations match well with simulations based on those parameters. There are small deviations called the dwarf galaxy problem and no one is inventing parameters to explain those, so what are you talking about?