Diogo S. Gorgulho

Inflation is the ultra-fast expansion of the universe in its first moments. It was driven by a field resembling a ball rolling down a hill. But there could have been a second, almost imperceptible ball nearby. The authors of this work considered exactly that scenario: a light spectator field (the axion), frozen at the top of its potential.

In the early Universe, tiny black holes could have been born — mountain-mass but atomic-nucleus-sized. Today they could serve as factories for dark matter. There are two mechanisms: the familiar evaporation (Hawking radiation) and the lesser-known superradiance.