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arXiv · 2306.08064

A string-inspired running-vacuum-model of cosmology, primordial-black-hole dark matter, and the current tensions in cosmological data

Nick E. Mavromatos
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Abstract

I review a cosmological model based on string-inspired gravity with anomalies and torsion, which leads to a cosmology of running-vacuum-model (RVM) type. It is argued that such a model can lead to observable, in principle, deviations from the standard $\Lambda$CDM paradigm of cosmology at late (modern) eras of the Universe evolution, contributing to an alleviation of the currently observed cosmological $H_0$ and structure-growth tensions, but also to a potential enhancement of the density of primordial black holes produced during inflation. The latter can thus play a role as dark matter components, and leave observable imprints in gravitational-wave patterns during the radiation-dominance era of the Universe.

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Nick E. Mavromatos. 2023-06-13. A string-inspired running-vacuum-model of cosmology, primordial-black-hole dark matter, and the current tensions in cosmological data. https://arxiv.org/abs/2306.08064

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