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Entropy of Microwave Background Radiation in Observable Universe

Yun-Song Piao
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Abstract

We show that the cosmological constant at late time places a bound on the entropy of microwave background radiation deposited in the future event horizon of a given observer, $S\leq S_{Λ_0}^{3/4}$. This bound is independent of the energy scale of reheating and the FRW evolution after reheating. We also discuss why the entropy of microwave background in our observable universe has its present value.

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Yun-Song Piao. 2006-07-17. Entropy of Microwave Background Radiation in Observable Universe. https://doi.org/10.1103/physrevd.74.047301

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