Contemporary gravitational waves from primordial black holes

TL;DR

This paper explores how primordial black holes in the early universe could generate a stochastic background of gravitational waves through their interactions, evaporation, and binary formation, with implications for GW detection.

Contribution

It analyzes the GW signals from primordial black holes considering their early universe interactions, evaporation, and binary formation, highlighting potential GW sources during PBH dominance.

Findings

GW from PBH interactions and evaporation could be detectable.

Binary formation among PBHs may produce significant gravitational waves.

Dilution of early universe GW signals depends on PBH dominance timing.

Abstract

Stochastic background of gravitational waves (GW) generated by the interactions between primordial black holes (PBH) in the early universe and by PBH evaporation is considered. If PBHs dominated in the cosmological energy density prior to their evaporation, GWs from the earlier stages (e.g. inflation) would be noticeably diluted. On the other hand, at the PBH dominance period they could form dense clusters where PBH binary formation might be significant. These binaries would be efficient sources of the gravitational waves.