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arXiv · 0903.1176

Beyond the Einstein Equation of State: Wald Entropy and Thermodynamical Gravity

Maulik K. Parikh·Sudipta Sarkar
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Abstract

We show that the classical equations of gravity follow from a thermodynamic relation, dQ = T dS, where S is taken to be the Wald entropy, applied to a local Rindler horizon at any point in spacetime. Our approach works for all diffeomorphism-invariant theories of gravity. This suggests that classical gravity may be thermodynamic in origin.

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Maulik K. Parikh, Sudipta Sarkar. 2009-03-06. Beyond the Einstein Equation of State: Wald Entropy and Thermodynamical Gravity. https://doi.org/10.3390/e18040119

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