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arXiv · 1408.4679

Evolution of Spacetime arises due to the departure from Holographic Equipartition in all Lanczos-Lovelock Theories of Gravity

Sumanta Chakraborty·T. Padmanabhan
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Abstract

In the case of general relativity one can interpret the Noether charge in any bulk region as the heat content $TS$ of its boundary surface. Further, the time evolution of spacetime metric in Einstein's theory arises due to the difference $(N_{sur}-N_{bulk})$ of suitably defined surface and bulk degrees of freedom. We show that this thermodynamic interpretation generalizes in a natural fashion to all Lanczos-Lovelock models of gravity. The Noether charge, related to time evolution vector field, in a bulk region of space is equal to the heat content $TS$ of the boundary surface with the temperature $T$ defined using local Rindler observers and $S$ being the Wald entropy. Using the Wald entropy to define the surface degrees of freedom $N_{sur}$ and Komar energy density to define the bulk degrees of freedom $N_{bulk}$, we can also show that the time evolution of the geometry is sourced by $(N_{sur}-N_{bulk})$. When it is possible to choose the foliation of spacetime such that metric is independent of time, the above dynamical equation yields the holographic equipartition for Lanczos-Lovelock gravity with $N_{sur}=N_{bulk}$. The implications are discussed.

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Sumanta Chakraborty, T. Padmanabhan. 2014-12-04. Evolution of Spacetime arises due to the departure from Holographic Equipartition in all Lanczos-Lovelock Theories of Gravity. https://doi.org/10.1103/physrevd.90.124017

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