In article , "Robert L.
Oldershaw" writes:

http://arxiv.org/abs/1603.00464

Title: Did LIGO detect dark matter?

Almost by definition, black-hole physics is the same no matter what the
black holes are "made of". So, of course, they could be made of dark
matter, or back issues of the ApJ, or whatever.

Possible evidence for primordial black holes as dark matter.

But the paper above is in no way evidence, not even partial evidence,
for primordial black holes as dark matter. It's saying they could be
dark matter, and that black holes in this mass range are not ruled out
(though I think the Lacy & Ostriker argument rules out them being a
substantial fraction of cosmological dark matter).

It seems to me that the paper is jumping on the bandwagon and trying to
get "LIGO" and "dark matter" into one paper. Not wrong, but not really
relevant.