English
Related papers

Related papers: Braneworld Remarks in Riemann-Cartan Manifolds

200 papers

The effective field equations on a 3-brane are established considering the massless bosonic sector of the type IIB string compactified on S^5. The covariant embedding formalism in a space endowed with Z_2-symmetry is applied. Recently the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Denis Gonta

We solve the Einstein equations in the Randall-Sundrum framework using an isotropic ansatz for the metric and obtain an exact expression to first order in the gravitational coupling. The solution is free from metric singularities away from…

High Energy Physics - Theory · Physics 2009-11-07 Ioannis Giannakis , Hai-cang Ren

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

We revisit the Riemann-Cartan geometry in the context of recent higher-dimensional theories of spacetime. After introducing the concept of torsion in a modern geometrical language we present some results that represent extensions of…

General Relativity and Quantum Cosmology · Physics 2009-04-01 C. Romero , J. B. Formiga , L. F. P. da Silva , F. Dahia

We present the generic junction conditions obeyed by a co-dimension one brane in an arbitrary background spacetime. As well as the usual Darmois-Israel junction conditions which relate the discontinuity in the extrinsic curvature to the to…

High Energy Physics - Theory · Physics 2009-11-07 R. A. Battye , B. Carter

We prove that for a large class of generalized Randall-Sundrum II type models the characterization of brane-gravity sector by the effective Einstein equation, Codazzi equation and the twice-contracted Gauss equation is equivalent with the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 László Á. Gergely

In the field equations of Einstein-Cartan theory with cosmological constant a static spherically symmetric perfect fluid with spin density satisfying the Weyssenhoff restriction is considered. This serves as a rough model of space filled…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Christian G. Boehmer

We compute the matching conditions for a general thick codimension 2 brane, a necessary previous step towards the investigation of gravitational phenomena in codimension 2 braneworlds. We show that, provided the brane is weakly curved, they…

High Energy Physics - Theory · Physics 2008-11-26 Ignacio Navarro , Jose Santiago

The solution of Einsteins equations for 4-brane embedded in 5-dimensional Anti-de-Sitter space-time is found. It is shown that the cosmological constant can provide the existence of ordinary 4-dimensional Newton's low and trapping of a…

High Energy Physics - Phenomenology · Physics 2009-10-31 Merab Gogberashvili

Braneworld cosmology for a domain wall embedded in the charged (Anti)-de Sitter-Schwarzschildblack hole of the five--dimensional Einstein-Gauss-Bonnet-Maxwell theory is considered. The effective Friedmann equation for the brane is derived…

High Energy Physics - Theory · Physics 2009-11-07 James E. Lidsey , Shin'ichi Nojiri , Sergei D. Odintsov

A solution of codimension 2 brane is found for which 4 dimensional Friedmann cosmology is recovered on the brane with time dependent tension, in the Einstein frame. The effective parameter $p/\rho$ of equation of state on the brane can be…

Astrophysics · Physics 2009-11-10 Hongsheng Zhang , Qi Guo , Rong-Gen Cai

Assuming an Einstein-Gauss-Bonnet theory of gravitation in a ($D \geq 5$)-dimensional spacetime with boundary, we consider the problem of the boundary dynamics given the matter Lagrangian on it. The resulting equation is applied in…

High Energy Physics - Theory · Physics 2010-04-06 Elias Gravanis , Steven Willison

We consider solutions of six dimensional Einstein equations with two compact dimensions. It is shown that one can introduce 3-branes in this background in such a way that the effective four dimensional cosmological constant is completely…

High Energy Physics - Theory · Physics 2009-11-10 Ignacio Navarro

This paper is devoted to the first systematic investigation of manifolds that are Einstein for a connection with skew symmetric torsion. We derive the Einstein equation from a variational principle and prove that, for parallel torsion, any…

Differential Geometry · Mathematics 2022-10-07 Ilka Agricola , Ana Cristina Ferreira

We use the conservation law of the stress-energy and spin tensors to study the motion of massive brane-like objects in Riemann-Cartan geometry. The world-sheet equations and boundary conditions are obtained in a manifestly covariant form.…

General Relativity and Quantum Cosmology · Physics 2010-10-12 Milovan Vasilic , Marko Vojinovic

We derive the full projected Einstein-Brans-Dicke gravitational equations associated with a n-dimensional brane embedded in a (n+1)-dimensional bulk. By making use of general conditions, as the positivity of the Brans-Dicke parameter and…

General Relativity and Quantum Cosmology · Physics 2011-03-28 J. M. Hoff da Silva , Roldao da Rocha

An alternative way of explaining astrophysical observations without dark matter is proposed. In the braneworld scenario, where our universe is visualised as a 4-dimensional hypersurface embedded in a higher dimensional spacetime, the…

Astrophysics · Physics 2007-05-23 Supratik Pal

We study Einstein metrics on smooth compact 4-manifolds with an edge-cone singularity of specified cone angle along an embedded 2-manifold. To do so, we first derive modified versions of the Gauss-Bonnet and signature theorems for arbitrary…

Differential Geometry · Mathematics 2017-05-17 Michael Atiyah , Claude LeBrun

We analyse the kinematics of cosmological spacetimes with nonzero torsion, in the framework of the classical Einstein-Cartan gravity. After a brief introduction to the basic features of spaces with non-vanishing torsion, we consider a…

General Relativity and Quantum Cosmology · Physics 2017-05-17 Klaountia Pasmatsiou , Christos G. Tsagas , John D. Barrow

We study the initial value problem in Einstein-Cartan theory which includes torsion and, therefore, a non-symmetric connection on the spacetime manifold. Generalizing the path of a classical theorem by Choquet-Bruhat and York for the…

General Relativity and Quantum Cosmology · Physics 2025-05-29 Paulo Luz , Filipe C. Mena