Por David Mulryne (Queen Mary University of London).

Primordial black holes (PBHs) might account for dark matter in the universe, or even account for some of the events seen at LIGO. Producing them from primordial fluctuations generated by inflation, however, requires a huge enhancement of power on short scales when compared with CMB scales. In this talk, I’ll first review inflation and how it provides an origin for structure in the universe, as well as how it could produce the seeds of PBHs. Then I’ll discuss a recent question that has arisen in the field: whether the enhancement of power needed to produce PBHs is self-consistent, or if back-reaction from the enhanced scales ruins inflation. On this question, I’ll discuss some recent results from our group at Queen Mary.