MOND disproved at large scales

[timmdeeg]

https://arxiv.org/pdf/2604.14327

Fig.1 and Fig.2 seem to show that MOND is disproved at large scales due to measurements of galaxy cluster velocities.

Supposed this holds, is it thinkable at all that MOND could be still true at galaxy scales?

 

[Hornbein]

MOND is just fitting a curve to data. As such it can't be proved or disproved.

 

[timmdeeg]

So is MOND a theoretical framework which makes predictions? If yes, should this framework hold scale independent?

In other words would you agree that either Gravity is modified or it isn't?

 

[mitchell porter]

It's standard MOND lore that MOND doesn't quite work for galaxy clusters - it has its own "missing mass" problem, or need for dark matter, on the cluster scale. This paper is actually extending that result to an even bigger, inter-cluster scale.

So one way to maintain MOND is to say that there is some extra mass there - sterile neutrinos, some other kind of dark matter (e.g. the Skordis-Zlosnik theorym ref 64 in this paper). There is also a recent paper coauthored by Pavel Kroupa arguing that they have found the MOND missing mass of galaxy clusters by using a different ansatz for inferring the distribution of cluster mass. Part of the MOND response to this paper, therefore, will be to see if either of these approaches can be scaled up to account for the new results.