How the Edge of Our Galaxy Defies Known Physics

It all started with Andromeda spinning faster than we think it should, according to our understanding. Thus, the idea of “there must be something more” was created. Maybe this elusive dark matter exists. Maybe it will answer those questions. 
However, also consider that our understanding is not complete. Perhaps all of those things we think are wrong are indeed correct, and our understanding is wrong. That is a lot more sensible than some messy hypothetical particle that must exist. Maybe it does exist, but that would be extremely convoluted not to mention egotistical. We’ve seen elsewhere the laws of physics break down and be defied... according to our understanding. That proves we don't know as much as we think we do. So it is more likely that, as proven, our understanding is not 100% than some particle we can’t find is the absurd round-about cause. Barking up the wrong tree. We should be studying Andromeda to figure out where, why & how our current understanding is incorrect.