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Related papers: Averaging in LRS class II spacetimes

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This paper is devoted in the study of the hydrostatic equilibrium of stellar structure in the framework of modified $f(R, T)$ gravity theory that allows the non-conservation of energy-momentum, with possible implications for several…

General Physics · Physics 2019-12-24 S. K. Maurya , Ayan Banerjee , Francisco Tello-Ortiz

Consider a bilinear interaction between two linear dispersive waves with a generic resonant structure (roughly speaking, space and time resonant sets intersect transversally). We derive an asymptotic equivalent of the solution for data in…

Analysis of PDEs · Mathematics 2015-06-17 Frederic Bernicot , Pierre Germain

We review the solution space for the field equations of Einstein's General Relativity for various static, spherically symmetric spacetimes. We consider the vacuum case, represented by the Schwarzschild black hole; the de…

General Relativity and Quantum Cosmology · Physics 2024-10-02 Andronikos Paliathanasis

Einstein's theory of general relativity models the physical universe using spacetimes which satisfy Einstein's gravitational field equations. To date, Einstein's theory has been enormously successful in modeling observed gravitational…

General Relativity and Quantum Cosmology · Physics 2016-10-21 James Isenberg

We classify all spacetimes with a closed rank-2 conformal Killing-Yano tensor. They give a generalization of Kerr-NUT-de Sitter spacetimes. The Einstein condition is explicitly solved and written as an indefinite integral. It is…

High Energy Physics - Theory · Physics 2008-11-26 Tsuyoshi Houri , Takeshi Oota , Yukinori Yasui

This is the main paper in a sequence in which we give a complete proof of the bounded $L^2$ curvature conjecture. More precisely we show that the time of existence of a classical solution to the Einstein-vacuum equations depends only on the…

Analysis of PDEs · Mathematics 2014-10-13 Sergiu Klainerman , Igor Rodnianski , Jeremie Szeftel

Recall that the usual Einstein metrics are those for which the first Ricci contraction of the covariant Riemann curvature tensor is proportional to the metric. Assuming the same type of restrictions but instead on the different contractions…

Differential Geometry · Mathematics 2010-05-11 Mohammed Larbi Labbi

We develop the General Theory of Relativity in a formalism with extended causality that describes physical interaction through discrete, transversal and localized pointlike fields. The homogeneous field equations are then solved for a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Manoelito M. de Souza , Robson N. Silveira

The inhomogeneous distribution of matter in the non-linear regime of galaxies, clusters of galaxies and voids is described by an exact, spherically symmetric inhomogeneous solution of Einstein's gravitational field equations, corresponding…

Astrophysics · Physics 2009-11-11 J. W. Moffat

We revisit the Kerr metric in Boyer-Lindquist coordinates and construct the corresponding class of nonstandard solutions of Einstein's equations. These solutions can be used to describe the outer part of spiral galaxies without assuming…

General Relativity and Quantum Cosmology · Physics 2013-01-11 Günter Scharf

Near the horizon of a black brane in Anti-de Sitter (AdS) space and near the AdS boundary, the long-wavelength fluctuations of the metric exhibit hydrodynamic behaviour. The gauge-gravity duality then relates the boundary hydrodynamics for…

High Energy Physics - Theory · Physics 2009-03-27 Ram Brustein , A. J. M. Medved

We derive a generalized deviation equation -- analogous to the well-known geodesic deviation equation -- for test bodies in General Relativity. Our result encompasses and generalizes previous extensions of the standard geodesic deviation…

General Relativity and Quantum Cosmology · Physics 2016-03-01 Dirk Puetzfeld , Yuri N. Obukhov

We propose and analyze a variant of the classic Polyak-Ruppert averaging scheme, broadly used in stochastic gradient methods. Rather than a uniform average of the iterates, we consider a weighted average, with weights decaying in a…

Machine Learning · Computer Science 2018-02-23 Gergely Neu , Lorenzo Rosasco

We investigate a general metric of the Kundt class of spacetimes in higher dimensions. Geometrically, it admits a non-twisting, non-shearing and non-expanding geodesic null congruence. We calculate all components of the curvature and Ricci…

General Relativity and Quantum Cosmology · Physics 2009-04-22 Jiri Podolsky , Martin Zofka

A class of second-order differential equations commonly arising in physics applications are considered, and their explicit hypergeometric solutions are provided. Further, the relationship with the Generalized and Universal Associated…

Mathematical Physics · Physics 2018-08-01 Keegan L. A. Kirk , Kyle R. Bryenton , Nasser Saad

An important question in mathematical relativity theory is that of the nature of spacetime singularities. The equations of general relativity, the Einstein equations, are essentially hyperbolic in nature and the study of spacetime…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Alan D. Rendall

We derive global weak solutions of Einstein's equations for spherically symmetric dust-filled space-times which admit shell-crossing singularities. In the marginally bound case, the solutions are weak solutions of a conservation law. In the…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Brien C. Nolan

We analyze the dynamics of a single spiral galaxy from a general relativistic viewpoint. We employ the known family of stationary axially-symmetric solutions to Einstein gravity coupled with dust in order to model the halo external to the…

General Relativity and Quantum Cosmology · Physics 2022-07-13 Davide Astesiano , Sergio L. Cacciatori , Federico Re

The exact global solution of the Einstein equations [Neugebauer & Meinel, Phys. Rev. Lett. 75 (1995) 3046] describing a rigidly rotating, self-gravitating disk is discussed. The underlying matter model is a perfect fluid in the limit of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Reinhard Meinel

We consider a system representing self-gravitating balls of dust in an expanding Universe. It is demonstrated that one can prescribe data for such a system at infinity and evolve it backward in time without the development of shocks or…

General Relativity and Quantum Cosmology · Physics 2022-06-29 Shabnam Beheshti , Mikael Normann , Juan Valiente Kroon