Possible generalizations within braneworld scenarios: Torsion fields
Nenhuma Miniatura disponível
Data
2012-03-01
Autores
Orientador
Coorientador
Pós-graduação
Curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Editor
Tipo
Capítulo de livro
Direito de acesso
Resumo
In this Chapter we introduce the aspects in which torsion can influence the formalismof braneworld scenarios in general, and also how it is possible to measure suchkind of effects, namely, for instance, the blackstring transverse area corrections andvariation of quasar luminosity due to those corrections. We analyze the projectedeffective Einstein equation in a 4-dimensional arbitrary manifold embedded in a 5-dimensional Riemann-Cartan manifold. The Israel-Darmois matching conditions areinvestigated, in the context where the torsion discontinuity is orthogonal to the brane.Unexpectedly, the presence of torsion terms in the connection does not modify suchconditionswhatsoever, despite of the modification in the extrinsic curvature and in theconnection. Then, by imposing the Z2-symmetry, the Einstein equation obtained viaGauss-Codazzi formalism is extended, in order to now encompass the torsion terms.We also show that the factors involving contorsion change drastically the effective Einsteinequation on the brane, as well as the effective cosmological constant. Also, wepresent gravitational aspects of braneworld models endowed with torsion terms bothin the bulk and on the brane. In order to investigate a conceivable and measurablegravitational effect, arising genuinely from bulk torsion terms, we analyze the variationin the black hole area by the presence of torsion. Furthermore, we extend the wellknown results about consistency conditions in a framework that incorporates branetorsion terms. It is shown, in a rough estimate, that the resulting effects are generallysuppressed by the internal space volume. This formalism providesmanageable models and their possible ramifications into some aspects of gravity in this context, and cognizablecorrections and physical effects as well. The torsion influences the braneworldscenario and we can check it by developing the bulk metric Taylor expansion aroundthe brane, which brings corrections in the blackstring transverse area. This generalizationis presented in order to better probe braneworld properties in a Riemann-Cartanframework, and it is also shown how the factors involving contorsion change the effectiveEinstein equation on the brane, the effective cosmological constant, and theirconsequence in a Taylor expansion of the bulk metric around the brane. © 2011 Nova Science Publishers, Inc. All rights reserved.
Descrição
Palavras-chave
Idioma
Inglês
Como citar
Classical and Quantum Gravity: Theory, Analysis and Applications, p. 477-506.