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arXiv · 2603.21881

Observational Constraints on Noncoincident $f(Q)$-Gravity with Matter-Gravity Coupling

Andronikos Paliathanasis
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Abstract

We investigate $f\left( Q\right) $-gravity with a matter-gravity coupling as a geometric dark energy candidate for the description of the late-time cosmic acceleration within a spatially flat Friedmann--Lema\^{\i}tre-Robertson-Walker geometry. We select a noncoincident connection that naturally follows from the general framework of cosmological models with nonzero spatial curvature. We present observational constraints for the simplest $f\left( Q\right) =f_{0}Q^{n}$ model using data from Supernovae, Baryon Acoustic Oscillations and Cosmic Chronometers. For different data combinations we found consistent constraints, with a best-fit value for the power-law index $n\simeq2$. A comparison with the $\Lambda$CDM model shows that the $f\left( Q\right) $-gravity leads to larger values for the likelihood, while Akaike's Information Criterion suggests statistical equivalence between the two models for most data combinations.

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Andronikos Paliathanasis. 2026-03-23. Observational Constraints on Noncoincident $f(Q)$-Gravity with Matter-Gravity Coupling. https://arxiv.org/abs/2603.21881

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