Speaker
Description
I will present the PBH reformation mechanism, wherein light PBHs can recollapse into heavier and more stable PBHs. Given a moderate initial abundance, light PBHs can initiate an early matter-dominated era before evaporating and reheating the radiation plasma. Structure formation is enabled during matter-domination, leading to clouds of PBHs growing and collapsing into heavier PBHs. Compared to the usual formation mechanism during the radiation era, the formation probability of PBHs is greatly increased and does not require any initial clustering. The heavier reformed PBH population could survive to the present day, emitting high energy cosmic rays while producing a coincident gravitational wave background, both potentially detectable by the next generation of experiments.