Mondays' DM meetings @ CP3

Tuesday December 20 2016

Sebastien Clesse will talk about:
'Could massive primordial black holes be the dark matter'

Abstract:
The recent detection by Advanced LIGO of gravitational waves (GW) from the merging of a binary black hole system sets new limits on the merging rates of massive primordial black holes (PBH) that could be identified to the dark matter in the Universe.   If PBH are regrouped in clusters with a similar density to the one observed in ultra-faint dwarf galaxies, merging rates are comparable to LIGO expectations.   We predict the existence of thousands of those dwarf galaxies where star formation is unlikely because of gas accretion onto PBH, which possibly provides a solution to the missing satellite and too-big-to-fail problems.   Besides, the model passes all the present astrophysical and cosmological constraints on PBH abundances, while being testable in a near future.  Such PBH could be produced in the early Universe, due to the collapse of large density fluctuations generated during a phase of hybrid inflation.   Advanced LIGO and future GW antennas, such as the LISA space interferometer, will be able measure the abundance, the clustering and the mass distribution of massive PBH, which could help to reveal their origin, with possible profound implications for cosmology and high energy physics.

This is the last journal club of the year.

Happy holidays!