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arXiv · 2511.18080

Primordial black hole driven cosmic acceleration

Konstantinos Dialektopoulos·Theodoros Papanikolaou·Vasilios Zarikas
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Abstract

We propose a natural mechanism for cosmic acceleration driven by primordial black holes (PBHs) with repulsive behavior, within a ''Swiss Cheese'' cosmological framework. Considering regular black hole spacetimes such as Hayward, Bardeen, and Dymnikova-as well as the singular Schwarzschild-de Sitter case-we consistently find a robust PBH-driven cosmic acceleration phase. This phase ends either at an energy scale set by the PBH parameters or through black hole evaporation. Notably, one finds that ultra-light PBHs with $m < 5 \times 10^8 \, {\rm g}$ can trigger exponential inflation with graceful exit and reheating. Additionally, PBHs with $m \sim 10^{12} \, {\rm g}$ and abundances $0.107 < \Omega_{\rm PBH}^{\rm eq} < 0.5$ near matter-radiation equality can act as an early dark energy component, offering a potential resolution to the Hubble tension.

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Konstantinos Dialektopoulos, Theodoros Papanikolaou, Vasilios Zarikas. 2025-11-22. Primordial black hole driven cosmic acceleration. https://doi.org/10.1142/s0218271825440158

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