> Shouldn't the regular matter influence the dark matter too? At that point doesn't it end up in the same distribution as the regular matter? No, not enough. T

> Shouldn't the regular matter influence the dark matter too? At that point doesn't it end up in the same distribution as the regular matter? No, not enough. This is a consequence of its interacting only gravitationally or via the weak force. Much of the distribution of visible matter is down to electromagnetic interactions that effectively allow it to collide and slow down, whereas dark matter naturally wouldn't do that, or at least would take a drastically longer time to do so.