Thermodynamical interpretation of the geometrical variables associated with null surfaces

@article{Chakraborty2015ThermodynamicalIO,
  title={Thermodynamical interpretation of the geometrical variables associated with null surfaces},
  author={Sumanta Chakraborty and Thanu Padmanabhan},
  journal={Physical Review D},
  year={2015},
  volume={92},
  pages={104011}
}
The emergent gravity paradigm interprets gravitational field equations as describing the thermodynamic limit of the underlying statistical mechanics of microscopic degrees of freedom of the spacetime. The connection is established by attributing a heat density Ts to the null surfaces where T is the appropriate Davies-Unruh temperature and s is the entropy density. The field equations can be obtained from a thermodynamic variational principle which extremises the total heat density of all null… 
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TLDR
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