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arXiv · 2306.03015

$f(Q)$-gravity and neutrino physics

Luís Atayde·Noemi Frusciante
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Abstract

Within the $f(Q)$-gravity framework we perform a phenomenological study of the cosmological observables in light of the degeneracy between neutrinos physics and the modified gravity parameter and we identify specific patterns which allow to break such degeneracy. We also provide separately constraints on the total mass of the neutrinos, $Σm_ν$, and on the effective number of neutrino species, $N_{\rm eff}$, using cosmic microwave background (CMB), baryon acoustic oscillation (BAO), redshift space distortion (RSD), supernovae (SNIa), galaxy clustering (GC) and weak gravitational lensing (WL) measurements. The strongest upper bound on the total mass of the neutrinos is found for the combination of CMB+BAO+RSD+SNIa and it is $Σm_ν<0.277$ eV at 95\% C.L. For the same combination of data we find $N_{\rm eff}=2.93^{+0.31}_{-0.34}$ at 95\% C.L. We also find that all combinations of data we consider, prefer a stronger gravitational interaction than $Λ$CDM. Finally, we consider the $χ^2$ and deviance information criterion statistics and find the $f(Q)+Σm_ν$ model to be statistically supported by data over the standard scenario. On the contrary $f(Q)+N_{\rm eff}$ is supported by CMB+BAO+RSD+SNIa but a moderate evidence against it is found with GC and WL data.

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Luís Atayde, Noemi Frusciante. 2023-06-05. $f(Q)$-gravity and neutrino physics. https://doi.org/10.1103/physrevd.107.124048

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