Primordial gravitational waves from black hole evaporation in standard and nonstandard cosmologies

Autor: Aurora Ireland, Stefano Profumo, Jordan Scharnhorst
Rok vydání: 2023
Předmět:
Zdroj: INSPIRE-HEP
ISSN: 2470-0029
2470-0010
DOI: 10.1103/physrevd.107.104021
Popis: Gravitons radiated from light, evaporating black holes contribute to the stochastic background of gravitational waves. The spectrum of such emission depends on both the mass and the spin of the black holes, as well as on the redshifting that occurs between the black hole formation and today. This, in turn, depends on the expansion history of the universe, which is largely unknown and unconstrained at times prior to the synthesis of light elements. Here, we explore the features of the stochastic background of gravitational waves from black hole evaporation under a broad range of possible early cosmological histories. The resulting gravitational wave signals typically peak at very high frequencies, and offer opportunities for proposed ultra-high frequency gravitational wave detectors. Lower-frequency peaks are also possible, albeit with a suppressed intensity that is likely well below the threshold of detectability. We find that the largest intensity peaks correspond to cosmologies dominated by fluids with equations of state that have large pressure-to-density ratios. Such scenarios can be constrained on the basis of violation of $\Delta N_{\rm eff}$ bounds.
Comment: 13 pages, 7 figures
Databáze: OpenAIRE