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arXiv · 2204.01015

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

Salvatore Capozziello·Rocco D'Agostino
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Abstract

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 \emph{a priori} assumptions on the cosmological model. To this purpose, we adopt a method based on rational Padé 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 $f(Q)=α+βQ^{n}$. Finally, possible deviations from the standard $Λ$CDM model are discussed.

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Salvatore Capozziello, Rocco D'Agostino. 2022-06-05. Model-independent reconstruction of $f(Q)$ non-metric gravity. https://doi.org/10.1016/j.physletb.2022.137229

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