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Inflation and nonequilibrium thermodynamics for the fluctuations in the infrared sector

Mauricio Bellini
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Abstract

In the framework of inflationary cosmology I study some aspects of nonequilibrium thermodynamics for the matter field fluctuations. The thermodynamic analysis is developed for de Sitter and power - law expansions of the universe. In both cases, I find that the heat capacity is negative leading respectively, to exponential and superexponential growth for the number of states in the infrared sector for de Sitter and power-law expansions of the universe. The spectrum for the matter field fluctuations can be understood from the background effective temperature when the horizon entry.

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Mauricio Bellini. 2000-11-21. Inflation and nonequilibrium thermodynamics for the fluctuations in the infrared sector. https://doi.org/10.1103/physrevd.63.087301

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