Connections between gravitational dynamics and thermodynamics

7th International Conference on Gravitation and Cosmology

Cai, R.-G.^1

State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics, Chinese Academy of Sciences, PO Box 2735, Beijing 100190, China^1

关键词: Black holes;    Einstein gravity;    Einstein's field equations;    Event horizon;    First law of thermodynamics;    Friedmann equation;    Hawking radiation;    Spacetime;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/484/1/012003/pdf
DOI  :  10.1088/1742-6596/484/1/012003

来源: IOP

【 摘 要 】

We have briefly summarized three aspects of connections between gravitational dynamics and thermodynamics by focusing on three kinds of spacetime horizon: Causal Rindler horizon of spacetime, black hole event horizon, and apparent horizon in a Friedmann-Robertson-Walker (FRW) universe. For the causal Rindler horizon, we have derived the Einstein's field equations from the Clausius relation. For black hole horizon in a static spherically symmetric spacetime, we have shown that at the black hole horizon, the Einstein's field equations can be cast to a form of the first law of thermodynamics. Applying to the Clausius relation to apparent horizon of a FRW universe, one is able to derive the Friedmann equations, not only in Einstein gravity, but also in Lovelock gravity. We have shown that there exists Hawking radiation associated with the apparent horizon in the FRW universe.