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arXiv · 2303.14031

Signature flip in deceleration parameter: A thermodynamic phase transition?

Tanima Duary·Narayan Banerjee·Ananda Dasgupta
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Abstract

Using the Hayward-Kodama temperature for the apparent horizon, it is found that matter content in the Universe is not thermodynamically stable, and the entry to the late accelerated expansion is actually a second order phase transition. The cosmological model used for the purpose is one that imitates the $\Lambda$CDM model, the favoured model for the present Universe.

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Tanima Duary, Narayan Banerjee, Ananda Dasgupta. 2023-03-24. Signature flip in deceleration parameter: A thermodynamic phase transition?. https://doi.org/10.1140/epjc%2Fs10052-023-11995-w

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