English
Related papers

Related papers: Black Holes, Ellipsoids, and Nonlinear Waves in Ps…

200 papers

A generalized geometric method is developed for constructing exact solutions of gravitational field equations in Einstein theory and generalizations. First, we apply the formalism of nonholonomic frame deformations (formally considered for…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sergiu I. Vacaru

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

We study spherically symmetric black hole solutions in a four-parameter Einstein-Cartan-type class of theories, called "torsion bigravity". These theories offer a geometric framework (with a metric and an independent torsionfull connection)…

General Relativity and Quantum Cosmology · Physics 2020-10-21 Vasilisa Nikiforova , Thibault Damour

We present, in closed analytic form, a general stationary, slowly rotating black hole, which is solution to a large class of alternative theories of gravity in four dimensions. In these theories, the Einstein-Hilbert action is supplemented…

General Relativity and Quantum Cosmology · Physics 2011-10-27 Paolo Pani , Caio F. B. Macedo , Luis C. B. Crispino , Vitor Cardoso

We study static, spherically symmetric black holes supported by Euler-Heisenberg theory of electrodynamics and coupled to two different modified theories of gravity. Such theories are the quadratic $f(R)$ model and Eddington-inspired…

General Relativity and Quantum Cosmology · Physics 2020-07-08 Merce Guerrero , Diego Rubiera-Garcia

We construct gravitational dynamics for Finsler spacetimes in terms of an action integral on the unit tangent bundle. These spacetimes are generalizations of Lorentzian metric manifolds which satisfy necessary causality properties. A…

General Relativity and Quantum Cosmology · Physics 2012-03-12 Christian Pfeifer , Mattias N. R. Wohlfarth

Higher derivative extensions of Einstein gravity are important within the string theory approach to gravity and as alternative and effective theories of gravity. H. L\"u, A. Perkins, C. Pope, K. Stelle [Phys.Rev.Lett. 114 (2015), 171601]…

General Relativity and Quantum Cosmology · Physics 2023-07-10 K. Kokkotas , R. A. Konoplya , A. Zhidenko

A number of recent papers have claimed to construct solutions of Einstein's equations describing black holes surrounded by dark-matter halos with empirically motivated density profiles such as the Navarro-Frenk-White, Burkert, Einasto,…

General Relativity and Quantum Cosmology · Physics 2025-12-09 S. V. Bolokhov

We present a comprehensive study of the quasinormal modes of a new class of nonlocal static and spherically symmetric black hole (BH) solutions within the framework of the revised Deser-Woodard theory of gravity. These solutions are…

General Relativity and Quantum Cosmology · Physics 2025-08-28 Rocco D'Agostino , Vittorio De Falco

A new method of construction of integral varieties of Einstein equations in three dimensional (3D) and 4D gravity is presented whereby, under corresponding redefinition of physical values with respect to anholonomic frames of reference with…

General Relativity and Quantum Cosmology · Physics 2010-02-03 Sergiu I. Vacaru

We synthesize and extend the previous ideas about appearance of both noncommutative and Finsler geometry in string theory with nonvanishing B--field and/or anholonomic (super) frame structures \cite{vstring,vstr2,vnonc,vncf}. There are…

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

The 'anholonomic frame' method (see gr-qc/0005025, gr-qc/0001060 and hep-th/0110250) is applied for constructing new classes of exact solutions of vacuum Einstein equations with off-diagonal metrics in 4D and 5D gravity. We examine several…

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

Various types of Lagrange and Finsler geometries and the Einstein gravity theory, and modifications, can be modelled by nonholonomic distributions on tangent bundles/ manifolds when the fundamental geometric objects are adapted to nonlinear…

Mathematical Physics · Physics 2013-07-26 Sergiu I. Vacaru

In the paper, only Static Spherically Symmetric space-times in four dimensions are considered within modified gravity models. The non-singular static metrics, including black holes not admitting a de Sitter core in the center and…

General Relativity and Quantum Cosmology · Physics 2024-10-07 A. S. Agrawal , Sergio Zerbini , B. Mishra

Based on the analogue spacetime programme, and many other ideas currently mooted in "quantum gravity", there is considerable ongoing speculation that the usual pseudo-Riemannian (Lorentzian) manifolds of general relativity might eventually…

General Relativity and Quantum Cosmology · Physics 2009-11-05 Jozef Skakala , Matt Visser

In this work, we extend for the first time the spherically symmetric Schwarzschild and Schwarzschild-De Sitter solutions with a Finsler-Randers-type perturbation which is generated by a covector $A_\gamma$. This gives a locally anisotropic…

General Relativity and Quantum Cosmology · Physics 2021-01-06 A. Triantafyllopoulos , S. Basilakos , E. Kapsabelis , P. C. Stavrinos

An approximate solution to Einstein's equations representing two widely-separated non-rotating black holes in a circular orbit is constructed by matching a post-Newtonian metric to two perturbed Schwarzschild metrics. The spacetime metric…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Kashif Alvi

Finsler geometry is just riemannian geometry without the quadratic restriction[1]. In this paper, we study the motion of massive(non-zero rest mass) and massless particles for schwarzschild metric in finsler spacetime in the case of two…

General Relativity and Quantum Cosmology · Physics 2018-01-08 V. Sai sumith Reddy

We construct four-dimensional gravity theories that resolve the Schwarzschild singularity and enable dynamical studies of nonsingular gravitational collapse. The construction employs a class of nonpolynomial curvature invariants that…

General Relativity and Quantum Cosmology · Physics 2025-10-22 Pablo Bueno , Pablo A. Cano , Robie A. Hennigar , Ángel J. Murcia

We construct a new class of exact solutions describing spacetimes possessing Lie algebroid symmetry. They are described by generic off-diagaonal 5D metrics embedded in bosonic string gravity and possess nontrivial limits to the Einstein…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Sergiu I. Vacaru