Title: Primordial black hole formation during reheating: an alternative mechanism
The formation of Primordial Black Holes (PBHs) during the reheating period following inflation is a possibility that has been studied since the emergence of the theory. This is mostly motivated by the dust-like stages of the background which generically appear during reheating, when a scalar field oscillates at the bottom of its potential. In this talk I will first review the standard approach to address PBH formation during reheating, presenting the latest results and pointing at the shortcomings. I will then present a new mechanism for PBH formation which considers the collapse of virialized scalar field structures, dubbed inflaton haloes and inflaton stars. I will show why this mechanism is more effective than the direct collapse of primordial fluctuations, and present some of its characteristics in particular examples.