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arXiv · 2301.01503

Addressing Cosmological Tensions by Non-Local Gravity

Filippo Bouchè·Salvatore Capozziello·Vincenzo Salzano
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Abstract

Alternative cosmological models have been under deep scrutiny in recent years, aiming to address the main shortcomings of the $\Lambda$CDM model. Moreover, as the accuracy of cosmological surveys improved, new tensions have risen between the model-dependent analysis of the Cosmic Microwave Background and lower redshift probes. Within this framework, we review two quantum-inspired non-locally extended theories of gravity, whose main cosmological feature is a geometrically driven accelerated expansion. The models are especially investigated in light of the Hubble and growth tension, and promising features emerge for the Deser--Woodard one. On the one hand, the cosmological analysis of the phenomenological formulation of the model shows a lowered growth of structures but an equivalent background with respect to $\Lambda$CDM. On the other hand, the study of the lensing features at the galaxy cluster scale of a new formulation of non-local cosmology, based on Noether symmetries, makes room for the possibility of alleviating both the $H_0$ and $\sigma_8$ tension. However, the urgent need for a screening mechanism arises for this non-local theory of gravity.

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Filippo Bouchè, Salvatore Capozziello, Vincenzo Salzano. 2023-01-04. Addressing Cosmological Tensions by Non-Local Gravity. https://doi.org/10.3390/universe9010027

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