Induced gravitational waves and baryon asymmetry fluctuations from primordial black hole formation
Abstract
We consider black hole formation due to the gravitational collapse produced by large density fluctuations during an epoch of reheating with a stiff equation of state and calculate the induced gravitational wave spectrum. By considering the existing bounds on the total energy density of gravitational waves today, we find constraints on the parameter space of this scenario. We also calculate the lepton asymmetry generated by metric perturbations via the chiral gravitational anomaly present in the Standard Model and find that, once the electroweak sphaleron processes have taken place, the large spectrum of scalar perturbations responsible for black hole formation induces a peak in the baryon asymmetry fluctuations on small scales.
 Publication:

Journal of Cosmology and Astroparticle Physics
 Pub Date:
 April 2024
 DOI:
 10.1088/14757516/2024/04/052
 arXiv:
 arXiv:2309.14993
 Bibcode:
 2024JCAP...04..052A
 Keywords:

 baryon asymmetry;
 inflation;
 primordial black holes;
 primordial gravitational waves (theory);
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 High Energy Physics  Phenomenology
 EPrint:
 40 pages, 12 figures. Minor clarifications, version accepted for publication in JCAP