Black holes are obvious answer to dark matter, why is that wrong? [duplicate]

Primordial Black Holes as dark matter candidate. I think this is interesting and new, in that there is a window of PBH masses (link from Count Iblis) And the first GW event from Ligo is right in that window.

This seems to be back in the news, (Well my latest copy of science news) Searching brings up previous papers (all behind pay walls.)

There have been some previous question here, and, more.

This seems like a nice solution, I'm mostly looking for other arXiv articles on the subject. Or reasons why it can't be so.

I edited my title to be a question.
Here's a link from one of my references.

marked as duplicate by ACuriousMind♦, heather, John Rennie black-holes StackExchange.ready(function() { if (StackExchange.options.isMobile) return; $('.dupe-hammer-message-hover:not(.hover-bound)').each(function() { var$hover = $(this).addClass('hover-bound'),$msg = $hover.siblings('.dupe-hammer-message');$hover.hover( function() { $hover.showInfoMessage('', { messageElement:$msg.clone().show(), transient: false, position: { my: 'bottom left', at: 'top center', offsetTop: -7 }, dismissable: false, relativeToBody: true }); }, function() { StackExchange.helpers.removeMessages(); } ); }); }); Sep 1 '16 at 6:15

• Can you summarize the latest information and ask a question? Not supposed to be simply asking for more references. – Bob Bee Aug 31 '16 at 16:12
• @BobBee, thanks, I certainly don't know enough about the subject to summarize it. I changed my title to ask a question. – George Herold Aug 31 '16 at 23:22
• You have not really explained how this is not a duplicate of Why can't dark matter be black holes? - you mention the question as a previous question, but it's not clear to be how this one is different. – ACuriousMind Aug 31 '16 at 23:44
• @CuriousMind The new papers he refers to claim that 20 to 100 solar mass BHs would evade the constraints noted in that question around 2012. The new papaers seem to be somewhat motivated by the fact that the merged BH that was observed in 2015 was from BHs in that mass range. The new claims have observational consequences like that mergers of those kinds of BHs come more from DM areas (halos, etc) than visible matter areas. A few years to invalidate. The source of those also requires some tuning on inflation, see the reference from Iblis below. Possible, for me still threading the needle. – Bob Bee Sep 1 '16 at 3:50
• @ACuriousMind, reading this paper, arxiv.org/abs/1603.00464, it seems to suggest that there is a window of BH masses that could still exist. That is interesting mostly because the first GW event was of two ~30 solar masses. Obviously we need more data, and a few more LIGO's spread around the world would give us some directional information. – George Herold Sep 1 '16 at 14:59