2025/10/08 by Keith R. Dienes, Dienes, Keith R., Lucien Heurtier +7 · 1 citation
Physics and Astronomy · #Accretion (finance) #Black Holes and Theoretical Physics #Cosmology and Gravitation Theories #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Mass spectrum #Population #Primordial black hole #Relativity and Gravitational Theory #Spectral line #Universe
paper · pdf · doi:10.48550/arxiv.2510.06551
published in arXiv (Cornell University) (Cornell University)
openalex publication_date 2025/10/08 · openalex created_date 2025/10/18 · openalex updated_date 2026/08/06
A variety of processes in the very early universe can give rise to a population of primordial black holes (PBHs) with an extended mass spectrum. For certain mass spectra of this sort, it has been shown that the evaporation of these PBHs into radiation can drive the universe toward an epoch of cosmological stasis which can persist for a significant number of e-folds of cosmological expansion. However, in general, the initial mass spectrum which characterizes a population of PBHs at the time of production can subsequently be distorted by processes such as mergers and accretion. In this paper, we examine the effects that these processes have on the spectra that lead to a PBH-induced stasis. Within such stasis models, we find that mergers have only a negligible effect on these spectra within the regime of interest for stasis. We likewise find that the effect of accretion is negligible in many cases of interest. However, we find that the effect of accretion on the PBH mass spectrum is non-negligible in situations in which this spectrum is particularly broad. In such situations, the stasis epoch is abridged or, in extreme cases, does not occur at all. Thus accretion plays a non-trivial role in constraining the emergence of stasis within scenarios which lead to extended PBH mass spectra.