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String-inspired running-vacuum cosmology, quantum corrections and the current cosmological tensions

Authors :
Mavromatos, Nick E.
Peracaula, Joan Solà
Gómez-Valent, Adrià
Publication Year :
2023

Abstract

In the context of a string-inspired running vacuum model (RVM) of cosmology with anomalies and torsion-induced axion-like fields, we discuss quantum corrections to the corresponding energy density, in approximately de Sitter eras, during which the Hubble parameter $H(t)$ varies very slowly with the cosmic time $t$. Such corrections arise either from graviton loops in the corresponding gravitational theory, or from path integration of massive quantum matter fields. They depend logarithmically on $H(t)$, in the form $H^n\, {\rm ln}(H^2)$, $n \in 2Z^+$. In the modern eras, for which the $n=2$ terns are dominant, such corrections may contribute to an alleviation of the currently observed cosmological $H_0$ and structure-growth tensions. In particular, we argue that such an effect is accomplished for a (dynamically-broken) supergravity-based RVM cosmological model. In the current de-Sitter era, for this case, rather surprisingly, the quantum graviton corrections dominate those due to matter fields, provided the scale of the primordial (pre-RVM inflation) dynamical breaking of local supersymmetry lies near the reduced Planck scale, which is a natural assumption in the context of the model.<br />Comment: 12 pages, latex (uses special (Springer Proceedings) macros), one pdf figure incorporated; Invited plenary talk (NEM) at 40th Conference on Recent Developments in High Energy Physics and Cosmology (HEP2023, 5-7 April 2023, U. of Ioannina (Greece)),based partly on e-Print:2305.15774 [gr-qc]. arXiv admin note: text overlap with arXiv:2306.08064.Corrections in references, no effects on conclusions

Details

Database :
arXiv
Publication Type :
Report
Accession number :
edsarx.2307.13130
Document Type :
Working Paper