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Related papers: Note on a class of anisotropic Einstein metrics

200 papers

It has often been suggested (especially by Carlip) that spacetime symmetries in the neighborhood of a black hole horizon may be relevant to a statistical understanding of the Bekenstein-Hawking entropy. A prime candidate for this type of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. J. M. Medved

We establish an algorithm that produces a new solution to the Einstein field equations, with an anisotropic matter distribution, from a given seed isotropic solution. The new solution is expressed in terms of integrals of known functions,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. D. Maharaj , M. Chaisi

We find obstructions to the existence of Einstein metrics of non-negative sectional curvature on a smooth closed simply connected manifold of any dimension. The results are achieved by combining the classical Morse theory of the loop space…

Differential Geometry · Mathematics 2007-05-23 Gabriel Paternain , Jimmy Petean

By assuming a particular mass function we find new exact solutions to the Einstein field equations with an anisotropic matter distribution. The solutions are shown to be relevant for the description of compact stars. A distinguishing…

General Relativity and Quantum Cosmology · Physics 2008-11-26 R. Sharma , S. D. Maharaj

We discuss a spatially homogeneous and anisotropic Bianchi type-I space-time with two fluids as the content of the Universe: matter and holographic dark energy in the framework of general relativity. To get the exact solutions of Einstein's…

General Relativity and Quantum Cosmology · Physics 2023-02-03 M. Koussour , M. Bennai

We show how the anisotropy resulting from the motion of an observer in an isotropic universe may be determined by measurements. This provides a means to identify inertial frames, yielding a simple resolution to the twins paradox of…

General Physics · Physics 2009-11-11 Subhash Kak

Different sequences of ellipsoids are represented on the ellipticity-rotation plane. The rotation parameter is defined as the ratio of kinetic energy related to the mean tangential equatorial velocity component to kinetic energy related to…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 R. Caimmi

This paper presents a hybrid numerical method to solve efficiently a class of highly anisotropic elliptic problems. The anisotropy is aligned with one coordinate-axis and its strength is described by a parameter $\eps \in (0,1]$, which can…

Numerical Analysis · Mathematics 2015-11-04 Anais Crestetto , Fabrice Deluzet , Claudia Negulescu

We consider exact solutions of Einstein equations defining static black holes parametrized by off-diagonal metrics which by anholonomic mappings can be equivalently transformed into some diagonal metrics with coefficients being very similar…

High Energy Physics - Theory · Physics 2007-05-23 Sergiu I. Vacaru , Evghenii Gaburov

We construct new classes of exact solutions in metric--affine gravity (MAG) with string corrections by the antisymmetric $H$--field. The solutions are parametrized by generic off--diagonal metrics possessing noncommutative symmetry…

High Energy Physics - Theory · Physics 2007-05-23 Sergiu I. Vacaru , Evghenii Gaburov

The origin of power asymmetry and other measures of statistical anisotropy on the largest scales of the universe, as manifested in Cosmic Microwave Background (CMB) and large-scale structure data, is a long-standing open question in…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-12 Pablo Fosalba , Enrique Gaztanaga

This paper makes a formal study of asymptotically hyperbolic Einstein metrics given, as conformal infinity, a conformal manifold with boundary. The space on which such an Einstein metric exists thus has a finite boundary in addition to the…

Differential Geometry · Mathematics 2017-08-09 Stephen E. McKeown

We find two new classes of exact solutions to the Einstein-Maxwell system of equations. The matter distribution satisfies a linear equation of state consistent with quark matter. The field equations are integrated by specifying forms for…

General Relativity and Quantum Cosmology · Physics 2015-06-23 Jefta M. Sunzu , Sunil D. Maharaj , Subharthi Ray

The isotropy of space is not a logical requirement but rather is an empirical question; indeed there is suggestive evidence that universe might be anisotropic. A plausible source of these anisotropies could be quantum gravity corrections.…

General Relativity and Quantum Cosmology · Physics 2021-07-07 Robert B. Mann , Idrus Husin , Hrishikesh Patel , Mir Faizal , Anto Sulaksono , Agus Suroso

A general form of a metric preserving all symmetries of a spherically symmetric gravitational field and angular momentum in spherical coordinates is obtained. Such metric may have $g_{01}(r)\neq 0$. The Newtonian limit uniquely defines…

General Physics · Physics 2019-12-18 Yaakov Friedman , Shmuel Stav

We start investigating the extension of the Horizon Quantum Mechanics to the case of spheroidal sources. We first study the location of trapping surfaces in space-times resulting from an axial deformation of static isotropic systems, and…

General Relativity and Quantum Cosmology · Physics 2018-06-13 R. Casadio , A. Giusti , R. Rahim

In this paper, we study a class of Finsler metrics called general (\alpha,\beta)-metrics, which are defined by a Riemannian metric and an 1-form. We construct some general (\alpha,\beta)-metrics with constant Ricci curvature.

Differential Geometry · Mathematics 2013-07-02 Zhongmin Shen , Changtao Yu

Einstein's theory of gravitation that governs the geometry of space-time, coupled with spectacular advance in cosmological observations, promises to deliver a `standard model' of cosmology in the near future. However, local geometry of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Tarun Souradeep

In this paper we study an anisotropic model generated from a particular Bianchi type-III metric, which is a generalization of G\"odel's metric and an exact solution of Einstein's field equations. We analyse type Ia supernova data, namely…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-02 R. S. Menezes , C. Pigozzo , S. Carneiro

In this work, we apply the anholonomic deformation method for constructing new classes of anisotropic cosmological solutions in Einstein gravity and/or generalizations with nonholonomic variables. There are analyzed four types of, in…

Mathematical Physics · Physics 2015-05-18 Sergiu I. Vacaru