Gravity and the Thermodynamics of Horizons

By T.Padmanabhan. 2003

300 citations recorded by the source corpus.

Spacetimes with horizons show a resemblance to thermodynamic systems and it is possible to associate the notions of temperature and entropy with them. Several aspects of this connection are reviewed in a manner appropriate for broad readership. The approach uses two essential principles: (a) the physical theories must be formulated for each observer entirely in terms of variables any given observer can access and (b) consistent formulation of quantum field theory requires analytic continuation to the complex plane. These two principles, when used together in spacetimes with horizons, are powerful enough to provide several results in a unified manner. Since spacetimes with horizons have a generic behaviour under analytic continuation, standard results of quantum field theory in curved spacetimes with horizons can be obtained directly (Sections III to VII). The requirements (a) and (b) also put strong constraints on the action principle describing the gravity and, in fact, one can obtain the Einstein-Hilbert action from the thermodynamic considerations (Section VIII). The review emphasises the thermodynamic aspects of horizons, which could be obtained from general principles and is expected to remain valid, independent of the microscopic description (‘statistical mechanics’) of horizons. We combine probabilities by multiplying, but we combine the actions ... by adding; ...... since the logarithm of the probability is necessarily negative, we may identify action provisionally with minus the logarithm of the statistical probability of the state... Eddington (1920) [1] The mathematicians can go beyond this Schwarzschild radius and get inside, but I would maintain that this inside region is not physical space, .... and should not be taken into account in any physical theory. Dirac (1962) [2]

Subfields: Atomic and Molecular Physics, and Optics, Nuclear and High Energy Physics, Statistical and Nonlinear Physics

View Paper: https://www.semanticscholar.org/paper/31a0e0b3739c21511fd19fe4482d9328d519fdd5

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Atomic and Molecular Physics, and Optics

In Nuclear and High Energy Physics

In Statistical and Nonlinear Physics

Citations in the corpus

Analogue Gravity (2005, background): “• Trans-Hawking versions of Hawking radiation, either as reformulations of the physics, or as alternative scenarios [30, 68, 130, 131, 150, 156, 167, 168, 169, 233, 289, 291, 325, 329, 333, 334, 340, 341, 350, 364].”
Black hole chemistry: thermodynamics with Lambda (2016, unknown): “See [130, 275, 276] for further results and references.”
Colloquium: Stimulating uncertainty: Amplifying the quantum vacuum with superconducting circuits (2011, background): “(29) (Padmanabhan, 2005).”
Hawking radiation as tunneling for extremal and rotating black holes (2005, methodology): “Alternatively, the so called method of complex paths has been introduced in several papers [9,11] (a review can be found in [21]).”