3 ms·

I do not think this is an argument in favor or against the existence of dark matter. I think it is a very surprising result either way. Only thing we know is th

by yiyus 9y ago

I do not think this is an argument in favor or against the existence of dark matter. I think it is a very surprising result either way. Only thing we know is that this galaxy is a very special fluke. It will surely be difficult to explain by non-dark-matter theories, but I do not think dark matter advocates are going to have any easier to explain why this galaxy (and, as far as we know, only this galaxy) doesn't have any dark matter. It will be exciting to see what explanations both camps come up with.

simias 9y ago
I'm no physicist or astronomer but as far as I can tell I don't think what you said makes complete sense. While it's true that it remains to be explained why a certain galaxy doesn't have the same amount of DM as the others at a glance it doesn't seem particularly implausible that such dramatic variation could theoretically happen depending on what DM truly is and how it ends up in galaxies in the first place. On the other hand you'd expect a modification to the theories of physics themselves like MOND would apply to all objects in the universe in the same way, if you find a galaxy where the model breaks down then the model is not good enough. That would be like finding a galaxy far away where gravity itself works differently, that'd be wild. So as far as I can tell it does seem to discredit something like MOND more than DM because you expect physical laws to be universal while it's plausible that DM could not be distributed equally everywhere.