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Related papers: Viscosity to entropy ratio at extremality

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String theory is used to compute the microscopic entropy for several examples of black holes in compactifications with $N=2$ supersymmetry. Agreement with the Bekenstein-Hawking entropy and the moduli-independent $N=2$ area formula is found…

High Energy Physics - Theory · Physics 2016-09-06 David M. Kaplan , David A. Lowe , Juan M. Maldacena , Andrew Strominger

We study the entropy of the black hole with torsion using the covariant form of the partition function. The regularization of infinities appearing in the semiclassical calculation is shown to be consistent with the grand canonical boundary…

General Relativity and Quantum Cosmology · Physics 2009-11-11 M. Blagojevic , B. Cvetkovic

We consider the entropy of four-dimensional near-extremal N=2 black holes. Without R^2-terms, the Bekenstein-Hawking entropy formula has the structure of the extremal black holes entropy with a shift of the charges depending on the…

High Energy Physics - Theory · Physics 2011-06-08 Eyal Gruss , Yaron Oz

We present some arguments in support of a {\it zero} entropy for {\it extremal} black holes. These rely on a combination of both quantum, thermodynamic, and statistical physics arguments. This result may shed some light on the nature of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Shahar Hod

We discuss the connection between different entropies introduced for black hole. It is demonstrated on the two-dimensional example that the (quantum) thermodynamical entropy of a hole coincides (including UV-finite terms) with its…

High Energy Physics - Theory · Physics 2016-08-24 Sergey Solodukhin

Black hole thermodynamics suggests that a black hole should have an entropy given by a quarter of the area of its horizon. Earlier calculations in U(1) loop quantum gravity have led to a dominant term proportional to the area, but there was…

General Relativity and Quantum Cosmology · Physics 2012-05-17 P. Mitra

Adopting thin film brick-wall model, we calculate the entropy of a nonuniformly rectilinearly accelerating non-stationary black hole expressed by Kinnersley metric. Because the black hole is accelerated, the event horizon is axisymmetric.…

General Relativity and Quantum Cosmology · Physics 2007-05-23 He Han , Zhao Zheng

Microscopic black holes explode with their temperature varying inversely as their mass. Such explosions would lead to the highest temperatures in the present universe, all the way to the Planck energy. Whether or not a quasi-stationary…

Astrophysics · Physics 2008-11-26 J. I. Kapusta

The question of what is the total entropy of the universe, how it compares to the maximal entropy of de Sitter space, and how it is distributed across the universe's components, bears considerable importance for a number of reasons. Here,…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-23 Stefano Profumo , Liam Colombo-Murphy , Gabriela Huckabee , Maya Diaz Svensson , Stuti Garg , Ishan Kollipara , Alison Weber

We derive the Bekenstein-Hawking entropy formula for four-dimensional Reissner-Nordstrom extremal black holes in type II string theory. The derivation is performed in two separate (T-dual) weak coupling pictures. One uses a type IIB bound…

High Energy Physics - Theory · Physics 2009-07-09 Clifford V. Johnson , Ramzi R. Khuri , Robert C. Myers

The relation between entropy and the area of the event horizon of a quantum blackhole in four dimensions is derived. The Reissner-Nordstrom metric for a non-rotating, charged black hole is shown to be modified by the addition of a new…

High Energy Physics - Theory · Physics 2009-07-03 B. B. Deo , P. K. Jena

The entropy of a quantum-statistical system which is classically approximated by a general stationary eternal black hole is studied by means of a microcanonical functional integral. This approach opens the possibility of including…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Erik A. Martinez

We define and compute the (analogue) shear viscosity to entropy density ratio $\tilde\eta/s$ for the QFTs dual to spherical AdS black holes both in Einstein and Gauss-Bonnet gravity in five spacetime dimensions. Although in this case, owing…

High Energy Physics - Theory · Physics 2018-01-09 Mariano Cadoni , Edgardo Franzin , Matteo Tuveri

The AdS_2\timesS^2 geometry of near-extremal Reissner-Nordstrom black holes can be described by an effective solvable model which allows to follow analytically the evaporation process including the backreaction. We find that an infinite…

High Energy Physics - Theory · Physics 2007-05-23 A. Fabbri , D. J. Navarro , J. Navarro-Salas

The entropy for two-dimensional black holes is obtained through the entropy function with the condition that the geometry approaches an $AdS_2$ spacetime in the near horizon limit. It is shown that the entropy is universal and proportional…

High Energy Physics - Theory · Physics 2010-10-27 Seungjoon Hyun , Wontae Kim , John J. Oh , Edwin J. Son

We use the relation between extremal black hole solutions in five- and in four-dimensional N=2 supergravity theories with cubic prepotentials to define the entropy function for extremal black holes with one angular momentum in five…

High Energy Physics - Theory · Physics 2010-10-27 Gabriel Lopes Cardoso , Johannes M. Oberreuter , Jan Perz

The investigation about the volume of a black hole is closely related to the quantum nature of the black hole. The entropy is a significant concept for this. A recent work by Majhi and Samanta [Phys. Lett. B 770 (2017) 314] after us…

General Relativity and Quantum Cosmology · Physics 2017-09-22 Baocheng Zhang

Black hole entropy is derived from a sum over boundary states. The boundary states are labeled by energy and momentum surface densities, and parametrized by the boundary metric. The sum over state labels is expressed as a functional…

General Relativity and Quantum Cosmology · Physics 2009-10-30 David Brown

We construct a new class of rotating AdS black hole solutions with non-compact event horizons of finite area in any dimension and study their thermodynamics. In four dimensions these black holes are solutions to gauged supergravity. We find…

High Energy Physics - Theory · Physics 2015-07-22 Robie A. Hennigar , David Kubiznak , Robert B. Mann

A seven parameter family of five-dimensional black hole solutions depending on mass, two angular momenta, three charges and the asymptotic value of a scalar field is constructed. The entropy is computed as a function of these parameters…

High Energy Physics - Theory · Physics 2009-09-17 J. C. Breckenridge , D. A. Lowe , R. C. Myers , A. W. Peet , A. Strominger , C. Vafa
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