Speaker
Описание
Abstract
Primordial black holes provide a distinctive theoretical laboratory for exploring the interplay between gravitational dynamics, nonequilibrium particle physics, and the thermal history of the early Universe. Across different mass regimes, their evolution is governed by competing processes, including gravitational accretion, cosmological expansion, and quantum evaporation. These processes may leave observable imprints on the formation of high-redshift supermassive black holes, stochastic gravitational-wave backgrounds, and primordial light-element abundances. In this talk, we investigate the multi-scale evolution of primordial black holes and its implications for fundamental physics. Within scalar–tensor theories of gravity, we consider nonminimal interactions between dark matter and a cosmological scalar field and examine their effects on relativistic transonic accretion. The resulting scalar-mediated force modifies the critical-point structure of the accretion flow and can substantially enhance black-hole mass growth. Under suitable conditions, this mechanism enables initially stellar-mass black-hole seeds to evolve toward supermassive scales within the limited cosmic time available at high redshifts. The associated modification of the black-hole mass distribution may also produce characteristic signatures in the stochastic gravitational-wave background. We further extend the investigation to light primordial black holes evaporating during neutrino decoupling and Big Bang nucleosynthesis. By combining greybody-corrected Hawking emission with momentum-dependent neutrino quantum kinetics, we examine the effects of nonthermal particle injection in scenarios involving sterile neutrinos and scalar-mediated dark-sector self-interactions. Particular emphasis is placed on the interplay between spectral distortions, the effective number of relativistic species, and charged-current neutron–proton conversion rates. Such effects may provide complementary probes of beyond-Standard-Model interactions, potentially revealing deviations in primordial element abundances even when integrated radiation-density observables remain close to their standard predictions. By examining gravitational growth and quantum evaporation in distinct primordial-black-hole mass regimes, this study develops a broader perspective on primordial black holes as multi-scale probes of gravity and early-Universe particle physics. The complementary roles of high-redshift observations, gravitational-wave measurements, and precision nucleosynthesis constraints are discussed as possible avenues for testing these scenarios. Keywords: Primordial black holes; Scalar–tensor gravity; Relativistic accretion; Hawking evaporation; Neutrino quantum kinetics; Big Bang nucleosynthesis.
Links
[1] J. Wu, D. Stepanenko, P. I. Pronin, L. Luo, C. Li, and J. Shi, “Primordial black holes as seeds for high-redshift supermassive black holes in scalar-tensor theories,” Physical Review D 114, 023059 (2026). https://doi.org/10.1103/xm6l-8n9z
[2] Wu, J., Luo, L., Yang, J., Ma, H., and Shi, J. (2026). Detector-weighted signatures of localized dissipative transitions in Kerr EMRIs. Classical and Quantum Gravity, 43, 175013.