Black Holes and the Second Law

2019 ◽  
pp. 303-306
Author(s):  
J. D. BEKENSTEIN
Keyword(s):  
1972 ◽  
Vol 4 (15) ◽  
pp. 737-740 ◽  
Author(s):  
J. D. Bekenstein
Keyword(s):  

2010 ◽  
Vol 33 (5-6) ◽  
pp. 292-295 ◽  
Author(s):  
J.A.S. Lima ◽  
S.H. Pereira ◽  
J.E. Horvath ◽  
Daniel C. Guariento

2021 ◽  
Vol 2021 (12) ◽  
Author(s):  
Brett McInnes

Abstract The Weak Gravity Conjecture arises from the assertion that all extremal black holes, even those which are “classical” in the sense of being very massive, must decay by quantum-mechanical emission of particles or smaller black holes. This is interesting, because some observed astrophysical black holes are on the brink of being extremal — though this is due to rapid rotation rather than a large electric or magnetic charge. The possibility that rotating near-extremal black holes might, in addition to radiating spinning particles, also bifurcate by emitting smaller black holes, has attracted much attention of late. There is, however, a basic question to be answered here: can such a bifurcation be compatible with the second law of thermodynamics? This is by no means clear. Here we show that, if there is indeed such a mechanism for bifurcations of AdS4-Kerr-Newman black holes, then this process can in fact satisfy the second law.


Author(s):  
John W. Moffat

A major question confronting physicists studying black holes was whether thermodynamics applied to them—that is, whether the black holes radiated heat and lost energy. Bekenstein considered heat and thermodynamics important for the interior of black holes. Based on the second law of thermodynamics, Hawking proposed that black holes evaporate over a very long time through what we now call Hawking radiation. This concept contradicts the notion that nothing can escape a black hole event horizon. Quantum physics enters into Hawking’s calculations, and he discovered the conundrum that the radiation would violate quantum mechanics, leading to what is called the information loss problem. These ideas are still controversial, and many physicists have attempted to resolve them, including Russian theorists Zel’dovich and Starobinsky. Alternative quantum physics interpretations of black holes have been proposed that address the thermodynamics problems, including so-called gravastars.


2011 ◽  
Vol 20 (02) ◽  
pp. 233-252 ◽  
Author(s):  
KHIREDDINE NOUICER

Adopting the thin layer improved brick wall method, we investigate the thermodynamics of a black hole embedded in a spatially flat Friedmann–Robertson–Walker universe. We calculate the temperature and the entropy at every apparent horizon for arbitrary solution of the scale factor. We show that the temperature and entropy display a nontrivial behavior as functions of time. In the case of black holes immersed in a universe driven by phantom energy, we show that for specific ranges of the equation-of-state parameter and apparent horizons the entropy is compatible with the D-bound conjecture, and even the null, dominant and strong energy conditions are violated. In the case of accretion of phantom energy onto a black hole with small Hawking–Hayward quasi-local mass, we obtain an equation-of-state parameter in the range w ≤ -5/3, guaranteeing the validity of the generalized second law.


2015 ◽  
Vol 24 (12) ◽  
pp. 1544014 ◽  
Author(s):  
Aron C. Wall

The Second Law of black hole thermodynamics is shown to hold for arbitrarily complicated theories of higher curvature gravity, so long as we allow only linearized perturbations to stationary black holes. Some ambiguities in Wald’s Noether charge method are resolved. The increasing quantity turns out to be the same as the holographic entanglement entropy calculated by Dong. It is suggested that only the linearization of the higher curvature Second Law is important, when consistently truncating a UV-complete quantum gravity theory.


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