Apparently, since all of that has been known for some time and still dark matter is not 100% guaranteed to not be MOND. I thought the Bullet Cluster was enough evidence against MOND but more knowledgeable folk than me think otherwise.wolram said:Do we need more proof of dark matter than this?:
https://en.wikipedia.org/wiki/Weak_gravitational_lensing
It turns out that when you only have one general class of evidence for a model (in this case, gravitational interactions), it's remarkably difficult to completely rule out alternative explanations. My understanding is that alternatives to dark matter are not very well-motivated by theory and tend to be much more complicated than many WIMP models. It also turns out to be much harder to get a modified gravity theory to work well with CMB, galaxy clusters, and galaxies using the same parameters (MOND has always had difficulty fitting CMB and cluster data).phinds said:Apparently, since all of that has been known for some time and still dark matter is not 100% guaranteed to not be MOND. I thought the Bullet Cluster was enough evidence against MOND but more knowledgeable folk than me think otherwise.