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arXiv · 2504.03470

Generalized entropic dark energy with spatial curvature

Sergei D. Odintsov·Simone D'Onofrio·Tanmoy Paul
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Abstract

In the realm of thermodynamics of apparent horizon, we construct a dark energy (DE) model from 4-parameter generalized entropy of apparent horizon in a spatially non-flat universe. In particular, considering a non-zero spatial curvature of the universe, we determine the dark energy fractional density and the dark energy equation of state (EoS) parameter (corresponding to the 4-parameter generalized entropy) in closed analytic forms. It turns out that the scenario can describe the correct thermal history of the universe, with the sequence of matter and dark energy epochs. Comparing with the $Λ$CDM model, the proposed generalized entropic DE model provides a higher value of the present Hubble parameter for a certain range of entropic parameter(s) leading to a possible resolution of the Hubble tension issue. This in turn leads to a positive spatial curvature of the universe. We confront the scenario with CC \& BAO, Pantheon+ \& SH0ES and joint analysis of the CC \& BAO \& Pantheon+ \& SH0ES datasets, which clearly depicts the phenomenological viability of the present model for some best fitted values of entropic parameter(s) that are indeed consistent with the resolution of Hubble tension.

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Sergei D. Odintsov, Simone D'Onofrio, Tanmoy Paul. 2025-04-04. Generalized entropic dark energy with spatial curvature. https://arxiv.org/abs/2504.03470

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