L. Atayde, S. Marques Nunes, N. Frusciante
Abstract
We study a minimal modified gravity scenario in the symmetric teleparallel (nonmetricity) formulation, focusing on an inverse nonmetricity term with f(Q)=Q+M4Q-1. The model does not introduce additional free parameters relative to the standard cosmological model ΛCDM, but modifies the late-time expansion and linear growth via an enhanced effective gravitational coupling. We identify key signatures: an enhanced matter power spectrum and cosmic microwave background (CMB) lensing, alongside a reduced late-time integrated Sachs-Wolfe effect and a shift in CMB peak positions. We confront the model with CMB data alone and in combination with baryon acoustic oscillations, redshift-space distortions, supernovae Ia, and DES large-scale structure data, considering both fixed minimal neutrino mass and varying Σmν. We find that the model typically prefers higher H0 than ΛCDM, alleviating the H0 tension, while its boosted growth tends to increase clustering amplitudes unless offset by larger neutrino masses when Σmν is free. Overall, CMB-only data provide at most weak statistical support compared to ΛCDM, whereas late-time measurements impose tight restrictions that largely remove any improvement, positioning this model as a minimal yet strongly constrained alternative to dark energy.
Keywords
General relativity / alternative theories of gravity
Physical Review D
Volume 114, Issue 024056, Page 11
2026 July
