Theoretically, what happens to the dark matter that surrounds galaxies when galaxies collide? ?

Question

Theoretically, what happens to the dark matter that surrounds galaxies when galaxies collide? ?

Answer 1

In theory, it would just combine. Like stars, the chance of any collision is probably rare.

Answer 2

The gravitational pull of the each galaxy's stars and dark matter twist, tear, and distort their original disk-like structures, leaving a single elliptical galaxy and lots of tidal debris after all is said and done.

Answer 3

It really depends, such as if or when the Andromeda galaxy and Milky Way galaxy collide they will pass through each other like ghosts, however cataclysmic events will occur, to try and determine what happens is almost impossible other then to say, negative matter will fuse and casue a larger galaxy or a completely new and inverted one  

Answer 4

It's a bit complicated.  The dark matter doesn't interact, except gravitationally.  The gas and dust in the two galaxies reacts right away - often coming to a stop.  But it has mass, so can slow the dark matter down.  A picture is better, so here's the link.