Geodesically complete cyclic cosmologies and entropy
arXiv:2305.06719 · doi:10.1140/epjc/s10052-024-12621-z
Abstract
We demonstrate that there exists a class of cyclic cosmological models, such that these models can in principle solve the problem of the entropy growth, and are at the same time geodesically complete. We thus show that some recently stated conclusions, according to which cyclic cosmologies solving the problem of entropy growth can not be geodesically complete due to the Borde-Guth-Vilenkin (BGV) theorem, are not justified. We also add a short conceptual discussion on entropy and cyclic cosmology, and present a detailed analysis of entropy density growth during periodic and non-periodic evolution for cyclic cosmologies.
arXiv comment18 pages, 2 figures, the major revision has been done and some dubious analysis with entropy free models have been omitted, also the article in this form has been accepted in EPJC
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