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arXiv · 1104.3194

The origin of entropy production in spacetime thermodynamics

Wei Gu·Rong-Xin Miao·Guang Wu
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Abstract

We find that the ambiguity term of approximate Killing vector field is responsible for the entropy production term. Without the ambiguity term, pure Einstein theory and $f(R)$ satisfy the relation of thermodynamic equilibrium. Considering such an ambiguity term of approximate Killing vector field, we can get the entropy production term and the entropy in $f(R)$ with a form defined by Jacobson. In pure Einstein theory, the shear term is the only geometric contribution of entropy production term, while in $f(R)$ it can also contribute. We believe our approach and conclusion can be generalized to other gravity theory.

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Wei Gu, Rong-Xin Miao, Guang Wu. 2011-04-16. The origin of entropy production in spacetime thermodynamics. https://arxiv.org/abs/1104.3194

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