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Related papers: Covariant entropy bound beyond general relativity

200 papers

Wald's entropy formula allows one to find the entropy of black holes' event horizon within any diffeomorphism invariant theory of gravity. When applied to general relativity, the formula yields the Bekenstein-Hawking result but, for any…

General Relativity and Quantum Cosmology · Physics 2015-08-24 Fayçal Hammad

We present new second derivative, generally covariant theories of gravity for spherically symmetric spacetimes (general covariance is in the $t-r$ plane) belonging to the class where the spherically symmetric Einstein-Hilbert theory is…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Rakesh Tibrewala

Motivated by the potential connection between metric-affine gravity and linear Generalized Uncertainty Principle (GUP) in the phase space, we develop a covariant form of linear GUP and an associated modified Poincar\'e algebra, which…

General Relativity and Quantum Cosmology · Physics 2024-04-15 Ahmed Farag Ali , Aneta Wojnar

Inspired by Verlinde's idea, some modified versions of entropic gravity have appeared in the literature. Extending them in a unified formalism, we derive the generalized gravitational equations accordingly. From gravitational equations, the…

High Energy Physics - Theory · Physics 2012-11-27 Tower Wang

We set up an Einstein-Gauss-Bonnet theory in four dimensions, based on the recent formulation of pure gravity with extra dimensions of vanishing metrical length [1]. In absence of torsion, the effective field equations depend only on the…

General Relativity and Quantum Cosmology · Physics 2022-02-11 Sandipan Sengupta

We define, by an integral of geometric quantities over a spherical shell of arbitrary radius, an invariant gravitational entropy. This definition relies on defining a gravitational energy and pressure, and it reduces at the horizon of both…

High Energy Physics - Theory · Physics 2015-06-03 Ram Brustein , A. J. M. Medved

We examine the idea that in quantum gravity, the entanglement entropy of a general region should be finite and the leading contribution is given by the Bekenstein-Hawking area law. Using holographic entanglement entropy calculations, we…

High Energy Physics - Theory · Physics 2015-06-15 Robert C. Myers , Razieh Pourhasan , Michael Smolkin

In its canonical formulation, general relativity is subject to gauge transformations that are equivalent to space-time coordinate changes of general covariance only when the gauge generators, given by the Hamiltonian and diffeomorphism…

General Relativity and Quantum Cosmology · Physics 2023-10-31 Martin Bojowald , Erick I. Duque

From a previous paper where we proposed a description of general relativity within the gravito-electromagnetic limit, we propose an alternative modified gravitational theory. As in the former version, we analyze the vector and tensor…

General Relativity and Quantum Cosmology · Physics 2022-05-03 Sergio Giardino

We present a semi-rigorous justification of Bekenstein's Generalized Second Law of Thermodynamics applicable to a universe with black holes present, based on a generic quantum gravity formulation of a black hole spacetime, where the bulk…

General Relativity and Quantum Cosmology · Physics 2024-04-03 Parthasarathi Majumdar

This paper has been withdrawn by the author after further work showed the proposed theoretical approach cannot fit planetary perihelion precession data. As presented, the theory doesn't fit gravitational light deflection by the sun either,…

General Physics · Physics 2014-03-28 Steven Kenneth Kauffmann

Extended Theories of Gravity can be considered a new paradigm to cure shortcomings of General Relativity at infrared and ultraviolet scales. They are an approach that, by preserving the undoubtedly positive results of Einstein's Theory, is…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Salvatore Capozziello , Mariafelicia De Laurentis

We study the covariant entropy bound in the context of gravitational collapse. First, we discuss critically the heuristic arguments advanced by Bousso. Then we solve the problem through an exact model: a Tolman-Bondi dust shell collapsing…

High Energy Physics - Theory · Physics 2009-11-10 Sijie Gao , Jose' P. S. Lemos

We present qualitative arguments in favor of an extension of the theory of the gravitational interaction beyond that resulting from the Hilbert-Einstein action. To this end we consider a locally conformal invariant theory of gravity,…

General Relativity and Quantum Cosmology · Physics 2023-02-07 Demosthenes Kazanas , Demetrios Papadopoulos , Dimitris Christodoulou

We present results from a numerical study of spherical gravitational collapse in shift symmetric Einstein dilaton Gauss-Bonnet (EdGB) gravity. This modified gravity theory has a single coupling parameter that when zero reduces to general…

General Relativity and Quantum Cosmology · Physics 2019-10-16 Justin L Ripley , Frans Pretorius

From a covariant Hamiltonian formulation, by using symplectic ideas, we obtain certain covariant boundary expressions for the quasilocal quantities of general relativity and other geometric gravity theories. The contribution from each of…

General Relativity and Quantum Cosmology · Physics 2014-11-17 C. M. Chen , J. M. Nester

We consider E. Verlinde's proposal that gravity is an entropic force -- we shall call this theory entropic gravity (EG) -- and reanalyze a recent claim that this theory is in contradiction with the observation of the gravitationally-bound…

High Energy Physics - Theory · Physics 2012-05-23 Masud Chaichian , Markku Oksanen , Anca Tureanu

We derive an extension of the Ryu-Takayanagi prescription for curvature squared theories of gravity in the bulk, and comment on a prescription for more general theories. This results in a new entangling functional, that contains a…

High Energy Physics - Theory · Physics 2015-06-17 Joan Camps

The Einstein theory of general relativity provides a peculiar example of classical field theory ruled by non-linear partial differential equations. A number of supplementary conditions (more frequently called gauge conditions) have also…

General Relativity and Quantum Cosmology · Physics 2016-11-23 Giampiero Esposito , Cosimo Stornaiolo

We review and extend the Gauge Vectors-Tensor gravity: a covariant theory of gravity composed of a metric and gauge fields, leading to simple second order partial differential equations of motion, whose Newtonian and strong limits coincide…

General Relativity and Quantum Cosmology · Physics 2014-06-03 Qasem Exirifard