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arXiv · 2210.09755

Generalized interacting Barrow Holographic Dark Energy: cosmological predictions and thermodynamic considerations

Abstract

We construct a generalized interacting model of Barrow Holographic Dark Energy (BHDE) with infrared cutoff being given by the Hubble horizon. We analyze the cosmological evolution of a flat Friedmann-Lema\^itre-Robertson-Walker Universe filled by pressureless dark matter, BHDE and radiation fluid. The interaction between the dark sectors of the cosmos is assumed of non-gravitational origin and satisfying the second law of thermodynamics and Le Chatelier-Braun principle. We study the behavior of various model parameters, such as the BHDE density parameter, the equation of state parameter, the deceleration parameter, the jerk parameter and the square of sound speed. We show that our model satisfactorily retraces the thermal history of the Universe and is consistent with current observations for certain values of parameters, providing an eligible candidate to describe dark energy. We finally explore the thermodynamics of our framework, with special focus on the validity of the generalized second law.

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BibTeXRIS

Giuseppe Gaetano Luciano, Jaume Giné. 2022-10-18. Generalized interacting Barrow Holographic Dark Energy: cosmological predictions and thermodynamic considerations. https://doi.org/10.1016/j.dark.2023.101256

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