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arXiv · 2508.00759

Can cosmic rotation resolve the Hubble tension? Constraints from CMB and large-scale structure

Micol Benetti·David A. Cook·Saulo Carneiro
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Abstract

We investigate a relativistic cosmological model with background rotation, sourced by a non-perfect fluid with anisotropic stress. A modified version of the CLASS Boltzmann code is employed to perform Monte Carlo Markov Chain analyses against Cosmic Microwave Background (CMB) and late-time datasets. The results show that current CMB data constrain the present-day rotation parameter to be negligible. As a consequence, the derived cosmological parameters remain consistent with the standard $\Lambda$CDM values. In contrast, late-time probes such as Type Ia supernovae (SNe) and Baryonic Acoustic Oscillations (BAO) allow for a higher level of rotation and yield an increased Hubble constant. However, this comes at the cost of a higher $\sigma_8$, which remains in tension with DES-Y3 measurement. Combining CMB, SNe and BAO data confirms the preference for non-rotation.

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Micol Benetti, David A. Cook, Saulo Carneiro. 2025-08-01. Can cosmic rotation resolve the Hubble tension? Constraints from CMB and large-scale structure. https://doi.org/10.1088/1475-7516%2F2026%2F02%2F043

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