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

We investigate f ( Q )-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–Lemaître-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 ( Q ) = 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 ≃ 2. A comparison with the ΛCDM model shows that the f ( Q )-gravity leads to larger values for the likelihood, while Akaike’s Information Criterion suggests statistical equivalence between the two models for most data combinations.