English
Related papers

Related papers: A note on splitting solutions in $4+1$ dimensional…

200 papers

We consider dynamics of a flat anisotropic Universe filled by a perfect fluid near a cosmological singularity in quadratic gravity. Two possible regimes are described -- the Kasner anisotropic solution and an isotropic "vacuum radiation"…

General Relativity and Quantum Cosmology · Physics 2017-01-04 A. Toporensky , D. Müller

We consider conditions for existence and stability of a static cosmological solution in quadratic gravity. It appears that such a solution for a Universe filled by only one type of perfect fluid is possible in a wide range of the equation…

General Relativity and Quantum Cosmology · Physics 2021-07-28 Daniel Muller , Alexey Toporensky

We consider numerically dynamics of a flat anisotropic Universe in Einstein-Gauss-Bonnet gravity with positive $\Lambda$ in dimensionalities 5+1 and 6+1. We identify three possible outcomes of the evolution, one singular and two…

General Relativity and Quantum Cosmology · Physics 2019-07-25 Dmitry Chirkov , Alexey Toporensky

We show that, in quadratic lagrangian theories of gravity, isotropic cosmological singularities are stable to the presence of small scalar, vector and tensor inhomogeneities. Unlike in general relativity, a particular exact isotropic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 John D. Barrow , Jonathan Middleton

Bouncing non-singular isotropic cosmological solutions are investigated in a simple model of scalar-tensor gravity. New families of such solutions are found and their properties are presented and analyzed using an effective potential as the…

General Relativity and Quantum Cosmology · Physics 2022-01-28 D. Polarski , A. A. Starobinsky , Y. Verbin

We study the stability of the isotropic vacuum Friedmann universe in gravity theories with higher-order curvature terms of the form $(R_{ab}R^{ab})^{n}$ added to the Einstein-Hilbert Lagrangian of general relativity on approach to an…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Jonathan Middleton , John D. Barrow

We investigate dynamics of (4+1) and (5+1) dimensional flat anisotropic Universe filled by a perfect fluid in the Gauss-Bonnet gravity. An analytical solutions valid for particular values of the equation of state parameter $w=1/3$ have been…

General Relativity and Quantum Cosmology · Physics 2014-11-20 I. V. Kirnos , A. N. Makarenko , S. A. Pavluchenko , A. V. Toporensky

In this work we implement the Minimal Geometric Deformation method to obtain the isotropic sector and the decoupler matter content of any anisotropic solution of the Einstein field equations with cosmological constant in $2+1$ dimensional…

General Relativity and Quantum Cosmology · Physics 2019-06-28 Ernesto Contreras

We propose a new approach to the Cosmological Constant Problem which makes essential use of an extra dimension. A model is presented in which the Standard Model vacuum energy ``warps'' the higher-dimensional spacetime while preserving 4D…

High Energy Physics - Theory · Physics 2009-09-15 Nima Arkani-Hamed , Savas Dimopoulos , Nemanja Kaloper , Raman Sundrum

We discuss the hypothesis of a fixed point for quantum gravity coupled to a scalar, in the limit where the scalar field goes to infinity, accompanied by a suitable scaling of the metric. We propose that no scalar potential is present for…

High Energy Physics - Theory · Physics 2010-05-25 C. Wetterich

A class of cosmological solutions of higher dimensional Einstein field equations with the energy-momentum tensor of a homogeneous, isotropic fluid as the source are considered with an anisotropic metric that includes the direct sum of a…

General Relativity and Quantum Cosmology · Physics 2013-10-24 Ozgur Akarsu , Tekin Dereli

We review a solution of the cosmological constant problem in a brane-world model with infinite-volume extra dimensions. The solution is based on a nonlinear generally covariant theory of a metastable graviton that leads to a large-distance…

High Energy Physics - Theory · Physics 2017-08-23 Gia Dvali , Gregory Gabadadze , M. Shifman

We investigated a flat multidimensional cosmological model in Gauss-Bonnet gravity in presence of a matter in form of perfect fluid. We found analytically new stationary regimes (these results are valid for arbitrary number of spatial…

General Relativity and Quantum Cosmology · Physics 2015-03-13 I. V. Kirnos , S. A. Pavluchenko , A. V. Toporensky

We consider dynamics of a flat anisotropic multidimensional cosmological model in Gauss-Bonnet gravity in the presence of a homogeneous magnetic field. In particular, we find conditions under which the known power-law vacuum solution can be…

General Relativity and Quantum Cosmology · Physics 2015-06-12 D. M. Chirkov , A. V. Toporensky

Anisotropic exponential cosmological solutions for a space of arbitrary dimension filled with ordinary matter in the 4th and 5th orders of Lovelock gravity are obtained. Also we have supposed a generalization of such solutions on an…

General Relativity and Quantum Cosmology · Physics 2017-02-24 Ilya V. Kirnos

We consider static cosmological solutions along with their stability properties in the framework of a recently proposed theory of massive gravity. We show that the modifcation introduced in the cosmological equations leads to several new…

General Relativity and Quantum Cosmology · Physics 2012-07-27 Luca Parisi , Ninfa Radicella , Gaetano Vilasi

We write down an anisotropic solution for a flat 5+1 dimensional Universe in Gauss-Bonnet gravity. In the model under investigation this solution replaces the generalized Kasner solution near a cosmological singularity.

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. Toporensky , P. Tretyakov

We introduce a large family of homogeneous and isotropic cosmological solutions in quadratic gravity which are singularity-free at early and late times. This kind of smooth solutions only emerges beyond the unstable de Sitter branch…

General Relativity and Quantum Cosmology · Physics 2024-12-16 M. Asorey , F. Ezquerro , M. Pardina

We consider a particular example of dynamical compactification of an anisotropic 7+1 dimensional Universe in Einstein - Gauss - Bonnet gravity. Starting from rather general totally anisotropic initial conditions a Universe in question…

General Relativity and Quantum Cosmology · Physics 2020-04-02 Dmitry Chirkov , Alex Giacomini , Alexey Toporensky

The existence and stability analysis of an inflationary solution in a $D+4$-dimensional anisotropic induced gravity is presented in this paper. Nontrivial conditions in the field equations are shown to be compatible with a cosmological…

High Energy Physics - Theory · Physics 2008-11-26 W. F. Kao
‹ Prev 1 2 3 10 Next ›