Nonequilibrium Black Hole Thermodynamics in Anti-de Sitter Spacetime

This work discusses the black hole thermodynamics in a weak dynamical Anti-de Sitter spacetime, which should be described by the nonequilibrium thermodynamics, because the metric depends on the time coordinate. Taking the Vaidya-Anti-de Sitter black hole spacetime as an example, the local entropy balance equations and principle of minimum entropy generation are derived, and finally, some irreversible effects in nonequilibrium thermodynamics are studied by using the Onsager reciprocal relation.

The Schwarzschild black hole in f(R) can exist superradiation phenomenon

For the relationship of the limit $y$ of the incident particle under the superradiance of the preset boundary (${\mu} = {y}{\omega}$),we find the relationship between black hole thermodynamics and superradiation, and use boundary conditions to establish the relationship between y and R. One of the modes under f(R) gravity,there is a possible solution.When r tends to infinity, as a coordinate transformation, y tends to 0. At that time, there is a potential barrier near the event horizon, that is, the Schwarzschild black hole under f(R) gravitation has superradiation at that time.

Bulk entropy is crucial to validate the second law of the extended black hole thermodynamics

The extended black hole thermodynamics in which the cosmological constant plays the role of pressure significantly enriches the phase structure of the theory. In order to understand the extended black hole thermodynamics more precisely, we let the value of the cosmological constant vary dynamically via tunneling from one vacuum to another in a black hole induced vacuum decay. In this process, entropy of the matter/energy released by a black hole is crucial to validate the second law of thermodynamics. In other words, without taking this bulk entropy into account, entropy associated with the black hole and cosmological horizons may not always increase. Since the bulk entropy is not represented by the black hole and the cosmological horizons, this result calls for a more careful interpretation of the holographic principle in which environmental effects are taken into account.

Black hole thermodynamics

The chapter presents the Penrose process, Hawking radiation, entropy and the laws of black hole thermodynamics. The Penrose process is derived and the area theorem is stated. A heuristic argument for the Hawking effect is given, emphasising a correct grasp of the concepts and the nature of the result. The Hawking effect and the Unruh effect are further discussed and linked together in a precise calculation. Evaporation of black holes is described. The information paradox is presented.

The Discrete and Continuous Quantum Field Theories and Natural Ultraviolet Cutting-off

Based on the results from black hole thermodynamics at all energy scales, this work demonstrates that, both for the discrete QFT previously introduced by the author and for QFT in continuous space-time, there is a natural ultraviolet applicable boundary (cut-off) distant from the Planck scales. It is important that this boundary exists irrespective of the fact in which pattern, perturbative or non-perturbative mode, QFT is studied. Different inferences from the obtained results are discussed, some statements are revised.

The Schwarzschild black hole in f(R) exist superradiation phenomenon

For the relationship of the limit $y$ of the incident particle under the superradiance of the preset boundary (${\mu} = {y}{\omega}$)and the limit $y$ of the incident particle under the Hawking radiation of the preset boundary (${y}{\mu} ={\omega}$),we find the relationship between black hole thermodynamics and superradiation, and use boundary conditions to establish the relationship between y and R. We find that the black hole energy and momentum tensor is transformed into an effective potential. When the effective potential has a potential barrier, then we know that the Schwarzschild black hole in f(R) exist superradiation phenomenon.