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arXiv · 1411.0897

Thick brane in $f(R)$ gravity with Palatini dynamics

D. Bazeia·L. Losano·R. Menezes·Gonzalo J. Olmo·D. Rubiera-Garcia
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Abstract

This work deals with modified gravity in five dimensional spacetime. We study a thick Palatini $f(R)$ brane, that is, a braneworld scenario described by an anti-de Sitter warped geometry with a single extra dimension of infinite extent, sourced by real scalar field under the Palatini approach, where the metric and the connection are regarded as independent degrees of freedom. We consider a first-order framework which we use to provide exact solutions for the scalar field and warp factor. We also investigate a perturbative scenario such that the Palatini approach is implemented through a Lagrangian $f(R)=R+εR^n$, where the small parameter $ε$ controls the deviation from the standard thick brane case.

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D. Bazeia, L. Losano, R. Menezes, Gonzalo J. Olmo, D. Rubiera-Garcia. 2015-11-23. Thick brane in $f(R)$ gravity with Palatini dynamics. https://doi.org/10.1140/epjc%2Fs10052-015-3803-0

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