2025/02/25 by Konstantinos F. Dialektopoulos, Theodoros Papanikolaou, Dialektopoulos, Konstantinos +3 · 7 citations
Physics and Astronomy · #Cosmology and Gravitation Theories #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Phenomenology (hep-ph) #Relativity and Gravitational Theory
paper · doi:10.48550/arxiv.2502.18352
openalex publication_date 2025/02/25 · openalex created_date 2025/10/15 · openalex updated_date 2026/07/28
We propose a novel and natural mechanism for cosmic acceleration driven by primordial black holes (PBHs) exhibiting repulsive behavior. Using a new ``Swiss Cheese'' cosmological approach, we demonstrate that this cosmic acceleration mechanism is a general phenomenon by examining three regular black hole spacetimes - namely the Hayward, the Bardeen and the Dymnikova spacetimes - as well as the singular de Sitter-Schwarzschild spacetime. Interestingly, by matching these black hole spacetimes with an isotropic and homogeneous expanding Universe, we obtain a phase of cosmic acceleration that ends at an energy scale characteristic to the black hole parameters or due to black hole evaporation. This cosmic acceleration mechanism can be relevant either to an inflationary phase with a graceful exit and reheating or to an early dark energy type of contribution pertinent to the Hubble tension. Remarkably, we find that ultra-light PBHs with masses m<5× 108g dominating the energy content of the Univese before Big Bang Nucleosynthesis, can drive a successful inflationary expansion era without the use of an inflaton field. Additionally, PBHs with masses m ∼ 1012g and abundances 0.107 < ΩeqPBH< 0.5, slightly before matter-radiation equality, can produce a substantial amount of early dark energy, helping to alleviate the H0 tension.