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arXiv · hep-th/0604182

Brane Models with a Ricci-Coupled Scalar Field

C. Bogdanos·A. Dimitriadis·K. Tamvakis
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Abstract

We consider the problem of a scalar field, non-minimally coupled to gravity through a $-ξϕ^{2}R$ term, in the presence of a Brane. Exact solutions, for a wide range of values of the coupling parameter $ξ$, for both $ϕ$-dependent and $ϕ$-independent Brane tension, are derived and their behaviour is studied. In the case of a Randall-Sundrum geometry, a class of the resulting scalar field solutions exhibits a folded-kink profile. We go beyond the Randall-Sundrum geometry studying general warp factor solutions in the presence of a kink scalar. Analytic and numerical results are provided for the case of a Brane or for smooth geometries, where the scalar field acts as a thick Brane. It is shown that finite geometries with warp factors that asymptotically decrease exponentially are realizable for a wide range of parameter values. We also study graviton localization in our setup and find that the localizing potential for gravitons with the characteristic volcano-like profile develops a local maximum located at the origin for high values of the coupling $ξ$.

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C. Bogdanos, A. Dimitriadis, K. Tamvakis. 2006-04-25. Brane Models with a Ricci-Coupled Scalar Field. https://doi.org/10.1103/physrevd.74.045003

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