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We present two new classes of magnetic brane solutions in Einstein-Maxwell-Gauss-Bonnet gravity with a negative cosmological constant. The first class of solutions yields an $(n+1)$-dimensional spacetime with a longitudinal magnetic field…

High Energy Physics - Theory · Physics 2009-11-10 M. H. Dehghani

By considering 5--dimensional cosmological models with a bulk filled with a perfect fluid and a cosmological constant, we have found regular instantonic solution which is free from any singularity at the origin of the extra--coordinate and…

High Energy Physics - Theory · Physics 2007-05-23 M. Bouhmadi-Lopez , P. F. Gonzalez-Diaz , A. Zhuk

We examine the idea that in quantum gravity, the entanglement entropy of a general region should be finite and the leading contribution is given by the Bekenstein-Hawking area law. Using holographic entanglement entropy calculations, we…

High Energy Physics - Theory · Physics 2015-06-15 Robert C. Myers , Razieh Pourhasan , Michael Smolkin

We consider 5D brane world models with broken global 4D Poincar\a'{e} invariance (4D part of the spacetime metric is not conformal to the Minkowski spacetime). The bulk is filled with the negative cosmological constant and may contain a…

General Relativity and Quantum Cosmology · Physics 2018-02-22 Ozgur Akarsu , Alexey Chopovsky , Maxim Eingorn , Seyed Hossein Fakhr , Alexander Zhuk

We construct models of static spherical distributions of perfect fluid in trace--free Einstein gravity theory. The equations governing the gravitational field are equivalent to the standard Einstein's equations however, their presentation…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Sudan Hansraj , Rituparno Goswami , George Ellis , Njabulo Mkhize

The existence of a set of $10$ Intrinsic Conformal Symmetries, which acts on three-dimensional hypersurfaces (spacelike or timelike), leads to the existence of two distinct families of 5D geometries. These models represent the general…

General Relativity and Quantum Cosmology · Physics 2024-12-06 Pantelis S. Apostolopoulos , Noeleen Naidoo

A generalized two-brane Randall-Sundrum warped braneworld model admits of solutions of the warp factor for both positive or negative cosmological constant on the visible 3-brane which can resolve the naturalness problem in connection with…

High Energy Physics - Theory · Physics 2010-05-12 Ratna Koley , Joydip Mitra , Soumitra SenGupta

Einstein gravity at $D\rightarrow 2$ limit can be obtained from the Kaluza-Klein procedure by taking the dimensions of the internal space to zero while keeping only the breathing mode. The resulting scalar-tensor theory can be further…

High Energy Physics - Theory · Physics 2023-03-29 Qi-Yuan Mao , H. Lu

We consider a scalar thick brane configuration arising in a 5D theory of gravity coupled to a self-interacting scalar field in a Riemannian manifold. We start from known classical solutions of the corresponding field equations and elaborate…

We study gravity in backgrounds that are smooth generalizations of the Randall-Sundrum model, with and without scalar fields. These generalizations include three-branes in higher dimensional spaces which are not necessarily Anti-de Sitter…

High Energy Physics - Theory · Physics 2009-07-09 Csaba Csaki , Joshua Erlich , Timothy J. Hollowood , Yuri Shirman

We investigate the embedding of four-dimensional branes in five-dimensional spaces. We firstly consider the case when the embedding space is a vacuum bulk whose energy-momentum tensor consists of a Dirac delta function with support in the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 F. Dahia , C. Romero

We have extended previous analysis of the bulk/brane supersymmetrizations involving non-zero brane mass terms of bulk fermions (gravitini) and twisting of boundary conditions. We have constructed new brane/bulk models that may be relevant…

High Energy Physics - Theory · Physics 2009-11-10 Zygmunt Lalak , Radoslaw Matyszkiewicz

Semiclassical Einstein's equation in five-dimension with a negative cosmological constant and conformally invariant bulk matter fields is examined in the brane world scenario with the S^1/Z_2 compactification. When numbers N_{b,f} of…

High Energy Physics - Theory · Physics 2009-10-31 Shinji Mukohyama

The field equations for static EGBM gravity are obtained and transformed to an equivalent form through a coordinate redefinition. A form for one of the metric potentials that generalises the spheroidal ansatz of Vaidya--Tikekar superdense…

General Relativity and Quantum Cosmology · Physics 2017-09-13 Sudan Hansraj

In this Chapter we introduce the aspects in which torsion can influence the formalism of braneworld scenarios in general, and also how it is possible to measure such kind of effects, namely, for instance, the blackstring transverse area…

General Relativity and Quantum Cosmology · Physics 2012-03-13 J M Hoff da Silva , Roldao da Rocha

Various attempts to go beyond the theory of General Relativity start from the assumption that spacetime is not a 4-dimensional but rather a higher-dimensional manifold. Among others, braneworld scenarios postulate that the spacetime we…

General Relativity and Quantum Cosmology · Physics 2024-01-31 Ivana Stojiljković , Dušan Đorđević , Aleksandra Gočanin , Dragoljub Gočanin

In recent papers on Randall-Sundrum D-braneworld model with Z_2 symmetry, it was shown that the effective gravity does not work as usual, that is, the gravity does not couple to the gauge field localised on the brane in a usual way. At…

High Energy Physics - Theory · Physics 2009-11-10 Keitaro Takahashi , Tetsuya Shiromizu

Interior perfect fluid solutions for the Reissner-Nordstrom metric are studied on the basis of a new classification scheme. It specifies which two of the fluid's characteristics are given functions and picks up accordingly one of the three…

General Relativity and Quantum Cosmology · Physics 2007-05-23 B. V. Ivanov

A nonstatic and circularly symmetric exact solution of the Einstein equations (with a cosmological constant $\Lambda$ and null fluid) in $2+1$ dimensions is given. This is a nonstatic generalization of the uncharged spinless BTZ metric. For…

General Relativity and Quantum Cosmology · Physics 2009-10-22 K. S. Virbhadra

We present a supersymmetric version of the two-brane Randall-Sundrum scenario, with arbitrary brane tensions T_1 and T_2, subject to the bound |T_{1,2}| \leq \sqrt{-6\Lambda_5}, where \Lambda_5 < 0 is the bulk cosmological constant.…

High Energy Physics - Theory · Physics 2011-08-03 Jonathan Bagger , Dmitry Belyaev