Model-independent reconstruction of f( Q) non-metric gravity

We consider gravity mediated by non-metricity, with vanishing curvature and torsion. The gravitational action, including an arbitrary function of the non-metric scalar, is investigated in view of characterizing the dark energy effects. In particular, we present a method to reconstruct the f( Q) action without resorting to a prioriassumptions on the cosmological model. To this purpose, we adopt a method based on rational Pade approximations, which provides a stable behaviour of the cosmographic series at high redshifts, alleviating the convergence issues proper of the standard approach. We thus describe how to reconstruct f( Q) through a numerical inversion procedure based on the current observational bounds on cosmographic parameters. Our analysis suggests that the best approximation for describing the accelerated expansion of the universe is represented by a scenario with f( Q) = alpha+ ss Q(n). Finally, possible deviations from the standard Lambda CDM model are discussed. (c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3).

Automated summary

This article investigates gravity mediated by non-metricity with vanishing curvature and torsion. The authors propose a method to reconstruct the gravitational action without assuming a specific cosmological model. The analysis suggests that the best approximation for describing the accelerated expansion of the universe is a scenario with a specific functional form for f(Q).