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Related papers: Quasilocal energy in modified gravity

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A quasi-local mass, typically defined as an integral over a spacelike $2$-surface $\Sigma$, should encode information about the gravitational field within a finite, extended region bounded by $\Sigma$. Therefore, in attempts to quantize…

General Relativity and Quantum Cosmology · Physics 2024-07-16 Bowen Zhao , Shing-Tung Yau , Lars Andersson

A definition of quasi-local energy in a gravitational field based upon its embedding into flat space is discussed. The outcome is not satisfactory from many points of view.

High Energy Physics - Theory · Physics 2018-11-09 Enrique Alvarez , Jesus Anero , Guillermo Milans del Bosch , Raquel Santos-Garcia

The energy of gravitational waves is a fundamental problem in gravity theory. The existing descriptions for the energy of gravitational waves, such as the well-known Isaacson energy-momentum tensor, suffer from several defects. Due to the…

General Relativity and Quantum Cosmology · Physics 2022-08-23 Rong-Gen Cai , Xing-Yu Yang , Long Zhao

In general relativity, the local gravitational energy is best characterised by the quasilocal mass. The small sphere limit of quasilocal mass provides us the most local notion of gravitational energy. In four dimensions, the limits were…

General Relativity and Quantum Cosmology · Physics 2019-09-27 Jinzhao Wang

Casimir energy in presence of a weak gravitational field is discussed taking into account the issues related to energy and its conservation in a curved background. It is well-known that there are inherent difficulties in defining energy in…

General Relativity and Quantum Cosmology · Physics 2020-11-24 Francesco Sorge

Motivated by the important work of Brown adn York on quasilocal energy, we propose definitions of quasilocal energy and momentum surface energy of a spacelike 2-surface with positive intrinsic curvature in a spacetime. We show that the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Chiu-Chu Melissa Liu , Shing-Tung Yau

Energy is at best defined quasilocally in general relativity. Quasilocal energy definitions depend on the conditions one imposes on the boundary Hamiltonian, i.e., how a finite region of spacetime is "isolated". Here, we propose a method to…

General Relativity and Quantum Cosmology · Physics 2016-10-19 Nezihe Uzun

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

It is shown that under proper conditions in an appropriate coordinate system with a suitable time slicing the Hamiltonian and the Einstein-Hilbert action including all necessary boundary terms can be written on shell in terms of the…

General Relativity and Quantum Cosmology · Physics 2023-10-13 Bjoern S. Schmekel

We modify previous quasi-local mass definition. The new definition provides expressions of the quasi-local energy, the quasi-local linear momentum and the quasi-local mass. And they are equal to the ADM expressions at spatial infinity.…

General Relativity and Quantum Cosmology · Physics 2009-12-15 Xiao Zhang

Consider the definition E of quasilocal energy stemming from the Hamilton-Jacobi method as applied to the canonical form of the gravitational action. We examine E in the standard "small-sphere limit," first considered by Horowitz and…

General Relativity and Quantum Cosmology · Physics 2016-08-25 J. D. Brown , S. R. Lau , J. W. York

The variant of quasiclassical (half-quantum) theory of gravity in strong gravitational field is presented. The exact solution of the problem of the renormalized energy-momentum tensor calculation is performed in terms of non-local…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yu. S. Grishkan , E. G. Vertogradova

The purpose of the classical Einstein and Landau-Lifshitz pseudotensors is for determining the gravitational energy. Neither of them can guarantee a positive energy in holonomic frames. In the small sphere approximation, it has been…

General Relativity and Quantum Cosmology · Physics 2009-09-28 Lau Loi So

Quasilocal definitions of stress-energy-momentum---that is, in the form of boundary densities (in lieu of local volume densities)---have proven generally very useful in formulating and applying conservation laws in general relativity. In…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Marius Oltean , Hossein Bazrafshan Moghaddam , Richard J. Epp

We point out an association between anomalies in the Hawking quasilocal mass (or, in spherical symmetry, in its better known version, the Misner-Sharp-Hernandez mass) and unphysical properties of the spacetime geometry. While anomalous…

General Relativity and Quantum Cosmology · Physics 2021-02-17 Valerio Faraoni , Andrea Giusti , Tyler F. Bean

In general relativity, quasi-local energy-momentum expressions have been constructed from various formulae. However, Newtonian theory of gravity gives a well known and an unique quasi-local mass expression (surface integration). Since…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yu-Huei Wu , Chih-Hung Wang

We extend the Brown and York notion of quasilocal energy to include coupled electromagnetic and dilaton fields and also allow for spatial boundaries that are not orthogonal to the foliation of the spacetime. We investigate how the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 I. S. Booth , R. B. Mann

I modify the quasilocal energy formalism of Brown and York into a purely Hamiltonian form. As part of the reformulation, I remove their restriction that the time evolution of the boundary of the spacetime be orthogonal to the leaves of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ivan S. Booth

Gravitating systems have no well-defined local energy-momentum density. Various quasilocal proposals have been made, however the center-of-mass moment (COM) has generally been overlooked. Asymptotically flat graviating systems have 10 total…

General Relativity and Quantum Cosmology · Physics 2007-05-23 James M. Nester , Feng-Feng Meng , Chiang-Mei Chen

Asymptotically flat gravitating systems have 10 conserved quantities, which lack proper local densities. It has been hoped that the teleparallel equivalent of Einstein's GR (TEGR, aka GR${}_{||}$) could solve this gravitational…

General Relativity and Quantum Cosmology · Physics 2016-11-09 James M. Nester , Fei-Hong Ho , Chiang-Mei Chen