Hacker News Reader

I am not convinced. What can possibly be said about two galaxies "hitting" each other if we observe only a sliver of time? Secondly, the stopping would happen because of gravity, and that would affect dark matter too.

View on HN

Gas clouds also interact electromagnetically: https://en.wikipedia.org/wiki/Bullet_Cluster

You shouldn't be convinced by one sentence saying that a conclusion was reached a few years back. But you also have no basis for confidence in the negation of that conclusion on the basis of that almost total lack of data or theory.

You can't honestly believe that teams of people with physics Ph.D.s just didn't address these questions - how do we infer from observational data, what do we infer from that data - so go read the paper.

Reply on news.ycombinator.com