Since dark matter does not interact with any other forces (unless you consider the gravitational force), I would like to know what happens to the momentum of the dark matter when falling into a black hole.
So: what happens to that momentum?
Update: I just read that normally there will be an accretion disk, inner disk heats up due to friction and speeds up the outer disk. This transferring of momentum cause mass to fall closer to the black hole but now I like to know what role does dark matter play for this case and also for another case considering if there is no accretion disk and assume static black hole? I know this is a bad question because the physics of dark matter is still new and on-going so please use whatever we have at hand then maybe someday I will fill in those blanks.