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It is shown that Einstein's equations on the brane can be received from the multi-dimensional vector field equations in pseudo-Euclidean space. The idea is based on the observation that the brane geometry can be equivalently described by…

High Energy Physics - Theory · Physics 2011-07-19 Merab Gogberashvili

The semiclassical Einstein-Langevin equations which describe the dynamics of stochastic perturbations of the metric induced by quantum stress-energy fluctuations of matter fields in a given state are considered on the background of the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Rosario Martin , Enric Verdaguer

We consider the four dimensional discontinuity generated by two identical pieces of a five dimensional space pasted along their edge (that is a "brane" in a "$Z_2$-symmetric" "bulk"). Using a four plus one decomposition of the Riemann…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Nathalie Deruelle , Joseph Katz

We study gravitational aspects of Brane-World scenarios. We show that the bulk Einstein equations together with the junction condition imply that the induced metric on the brane satisfies the full non-linear Einstein equations with a…

High Energy Physics - Theory · Physics 2009-10-31 Sebastian de Haro , Kostas Skenderis , Sergey N. Solodukhin

In this article we study a generalization of DGP scenarios, where the induced gravity is given by a $f(R)$ term. We obtain the effective gravitational equations and the effective FLRW cosmological equation on the brane of this model. We…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Joel Saavedra , Yerko Vásquez

In semiclassical gravity the back-reaction of the classical gravitational field interacting with quantum matter fields is described by the semiclassical Einstein equations. A criterion for the validity of semiclassical gravity based on the…

General Relativity and Quantum Cosmology · Physics 2011-08-04 E. Verdaguer

We present the effective equations to describe the four-dimensional gravity of a brane world, assuming that a five-dimensional bulk spacetime satisfies the Einstein equations and gravity is confined on the $Z_2$ symmetric brane. Applying…

General Relativity and Quantum Cosmology · Physics 2011-05-05 Kei-ichi Maeda , Shuntaro Mizuno , Takashi Torii

Recently, we presented a unified way of analysing classical cosmological perturbation in generalized gravity theories. In this paper, we derive the perturbation spectrums generated from quantum fluctuations again in unified forms. We…

General Relativity and Quantum Cosmology · Physics 2014-11-17 J. Hwang

Using both the Born-Oppenheimer idea and the de Broglie-Bohm interpretation of wavefunction we represent in a different way the semiclassical quantum gravity from the Wheeler-DeWitt equation in an oscillating regime which can preserve…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Sang Pyo Kim

We establish a well-posedness theory for the f(R) theory of modified gravity, which is a generalization of Einstein's theory of gravitation. The scalar curvature R of the spacetime, which arises in the integrand of the Einstein-Hilbert…

Analysis of PDEs · Mathematics 2014-12-30 Philippe G. LeFloch , Yue Ma

We consider brane cosmology when the 4D Ricci scalar term is added to the 5D Einstein-Hilbert action and discuss the role that the addition of this term has on the brane-bulk system. The induced brane dynamics is shown to be the usual…

General Relativity and Quantum Cosmology · Physics 2008-12-19 M. La Camera

It has been proposed recently to consider in the framework of cosmology an extension of the semiclassical Einstein's equations in which the Einstein tensor is considered as a random function. This paradigm yields a hierarchy of equations…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Claudio Dappiaggi , Alberto Melati

A brief introduction is given to the subject of brane induced gravity. The 5D example is discussed in detail. The 4D laws of gravity are obtained on a brane embedded in an infinite volume extra space, where the problem of stabilization of…

High Energy Physics - Theory · Physics 2008-11-26 Gregory Gabadadze

The semiclassical corrections to the Cardy-Verlinde entropy of a five-dimensional Schwarzschild de-Sitter black hole (SdS_5) are explicitly evaluated. These corrections are considered within the context of KKW analysis and arise as a result…

High Energy Physics - Theory · Physics 2009-11-10 Mohammad R. Setare , Elias C. Vagenas

In the first part of this work we review the equations of motion for the brane presented in Friedmann-Robertson-Walker (FRW) form, when bulk is five-dimensional (A)dS Black Hole. The spacelike (timelike) FRW brane equations are considered…

High Energy Physics - Theory · Physics 2009-09-17 Shin'ichi Nojiri , Sergei D. Odintsov , Sachiko Ogushi

Semiclassical Einstein-Langevin equations for arbitrary small metric perturbations conformally coupled to a massless quantum scalar field in a spatially flat cosmological background are derived. Use is made of the fact that for this problem…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Antonio Campos , Enric Verdaguer

We derive the four-dimensional field equations for the induced metric and scalar field on the world-volume of a 3-brane in a five-dimensional bulk with Einstein gravity plus a self-interacting scalar field. We calculate the effective…

High Energy Physics - Theory · Physics 2009-10-31 Kei-ichi Maeda , David Wands

We study cosmological perturbations generated from quantum fluctuations in multi-field inflationary scenarios in generalized Einstein theories, taking both adiabatic and isocurvature modes into account. In the slow-roll approximation,…

Astrophysics · Physics 2009-11-07 Alexei A. Starobinsky , Shinji Tsujikawa , Jun'ichi Yokoyama

We extend the Induced Matter Theory of gravity (IMT) to 5D curved spacetimes by using the Weitzenb\"ock representation of connections on a 5D curved spacetime. In this representation the 5D curvature tensor becomes null, so that we can make…

General Relativity and Quantum Cosmology · Physics 2022-06-29 Jesús Martín Romero , Mauricio Bellini

In the first part of this paper, we show that the semiclassical Einstein-Langevin equation, introduced in the framework of a stochastic generalization of semiclassical gravity to describe the back reaction of matter stress-energy…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Rosario Martin , Enric Verdaguer