English
Related papers

Related papers: Entropy for curvature squared gravity using surfac…

200 papers

The quadratic gravity constraints are reformulated in terms of the Newman-Penrose-like quantities. In such a frame language, the field equations represent a linear algebraic system for the Ricci tensor components. In principle, a procedure…

General Relativity and Quantum Cosmology · Physics 2023-02-08 Robert Svarc , Alena Pravdova , David Miskovsky

We propose a thermodynamically motivated measure of gravitational entropy based on the Bel-Robinson tensor, which has a natural interpretation as the effective super-energy-momentum tensor of free gravitational fields. The specific form of…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Timothy Clifton , George F R Ellis , Reza Tavakol

We consider the static, spherically symmetric black hole solutions in bigravity theory for minimal model with a condition $f_{\mu \nu} = C^{2} g_{\mu \nu}$ and evaluate the entropy for black holes. In this condition, we show that there…

High Energy Physics - Theory · Physics 2013-08-27 Taishi Katsuragawa , Shin'ichi Nojiri

We address the problem of the energy conditions in modified gravity taking into account the additional degrees of freedom related to scalar fields and curvature invariants. The latter are usually interpreted as generalized {\it geometrical…

General Relativity and Quantum Cosmology · Physics 2015-05-05 José P. Mimoso , Francisco S. N. Lobo , Salvatore Capozziello

The holographic entanglement entropy functional for higher-curvature gravities involves a weighted sum whose evaluation, beyond quadratic order, requires a complicated theory-dependent splitting of the Riemann tensor components. Using the…

High Energy Physics - Theory · Physics 2021-05-05 Pablo Bueno , Joan Camps , Alejandro Vilar López

In any quantum theory of gravity we do expect corrections to Einstein gravity to occur. Yet, at fundamental level, it is not apparent what the most relevant corrections are. We argue that the generic curvature square corrections present in…

High Energy Physics - Theory · Physics 2011-02-09 Ishwaree P. Neupane , Naresh Dadhich

We calculate quantum gravitational corrections to the entropy of black holes using the Wald entropy formula within an effective field theory approach to quantum gravity. The corrections to the entropy are calculated to second order in…

High Energy Physics - Theory · Physics 2021-09-22 Xavier Calmet , Folkert Kuipers

We consider classical Euclidean gravity solutions with a boundary. The boundary contains a non-contractible circle. These solutions can be interpreted as computing the trace of a density matrix in the full quantum gravity theory, in the…

High Energy Physics - Theory · Physics 2015-06-15 Aitor Lewkowycz , Juan Maldacena

By generalizing different recent works to the context of higher curvature gravity, we provide a unifying framework for three related results: (i) If an asymptotically AdS spacetime computes the entanglement entropies of ball-shaped regions…

High Energy Physics - Theory · Physics 2018-05-22 Felix M. Haehl , Eliot Hijano , Onkar Parrikar , Charles Rabideau

We extend the thermodynamic derivation of gravity in the Jacobson framework by generalizing the Clausius relation through a nontrivial entropy functional. We show that entropy deformations appear as modifications of the effective…

General Relativity and Quantum Cosmology · Physics 2026-04-14 H. R. Fazlollahi

We study regular spacelike warped black holes in the three dimensional general massive gravity model, which contains both the gravitational Chern-Simons term and the linear combination of curvature squared terms characterizing the new…

High Energy Physics - Theory · Physics 2010-09-01 Erik Tonni

We derive the evolution equation for the second order curvature perturbation using standard techniques of cosmological perturbation theory. We do this for different definitions of the gauge invariant curvature perturbation, arising from…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-09 Pedro Carrilho , Karim A. Malik

We treat D-dimensional black holes with Killing horizon for extended Gauss-Bonnet gravity. We use Carlip method and impose boundary conditions on horizon what enables us to identify Virasoro algebra and evaluate its central charge and…

High Energy Physics - Theory · Physics 2009-11-07 M. Cvitan , S. Pallua , P. Prester

In loop quantum gravity, the area element of embedded spatial surfaces is given by a well-defined operator. We further characterize the quantized geometry of such surfaces by proposing definitions for operators quantizing scalar curvature…

General Relativity and Quantum Cosmology · Physics 2018-09-26 David Grüber , Hanno Sahlmann , Thomas Zilker

The paper considers a set of equations describing the static isotropic gravity field of a macroscopic body within the framework of the theory of gravity with a constraint. A general approximate solution of these equations is obtained. The…

General Relativity and Quantum Cosmology · Physics 2024-02-08 Alexander P. Sobolev , Aleksey Sobolev

Since the seminal work of Verlinde, the idea that gravity may be an emergent force of entropic origin has gained widespread attention. Many generalizations of this key idea have been considered in the literature, starting from well-known…

General Relativity and Quantum Cosmology · Physics 2023-06-19 Kamel Ourabah

We propose a new class of vector fields to construct a conserved charge in a general field theory whose energy momentum tensor is covariantly conserved. We show that there always exists such a vector field in a given field theory even…

General Relativity and Quantum Cosmology · Physics 2021-12-03 Sinya Aoki , Tetsuya Onogi , Shuichi Yokoyama

In arXiv:1310.5713 and arXiv:1310.6659 a formula was proposed as the entanglement entropy functional for a general higher-derivative theory of gravity, whose lagrangian consists of terms containing contractions of the Riemann tensor. In…

High Energy Physics - Theory · Physics 2015-02-24 Arpan Bhattacharyya , Menika Sharma

On a manifold with boundary, the constraint algebra of general relativity may acquire a central extension, which can be computed using covariant phase space techniques. When the boundary is a (local) Killing horizon, a natural set of…

General Relativity and Quantum Cosmology · Physics 2010-04-28 S. Carlip

We consider generalized energy conditions in modified theories of gravity by taking into account the further degrees of freedom related to scalar fields and curvature invariants. The latter are usually recast as generalized {\it geometrical…

General Relativity and Quantum Cosmology · Physics 2014-02-14 Salvatore Capozziello , Francisco S. N. Lobo , José P. Mimoso