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arXiv · 2010.07914

Equivalence of non-minimally coupled cosmologies by Noether symmetries

Francesco Bajardi·Salvatore Capozziello
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Abstract

We discuss non-minimally coupled cosmologies involving different geometric invariants. Specifically, actions containing a non-minimally coupled scalar field to gravity described, in turn, by curvature, torsion and Gauss--Bonnet scalars are considered. We show that couplings, potentials and kinetic terms are determined by the existence of Noether symmetries which, moreover, allows to reduce and solve dynamics. The main finding of the paper is that different non-minimally coupled theories, presenting the same Noether symmetries, are dynamically equivalent. In other words, Noether symmetries are a selection criterion to compare different theories of gravity.

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Francesco Bajardi, Salvatore Capozziello. 2020-10-15. Equivalence of non-minimally coupled cosmologies by Noether symmetries. https://doi.org/10.1142/s0218271820300153

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