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arXiv · 1411.3552

Spherically Symmetric Thick Branes Cosmological Evolution

Alex E. Bernardini·R. T. Cavalcanti·Roldao da Rocha
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Abstract

Spherically symmetric time-dependent solutions for the 5D system of a scalar field canonically coupled to gravity are obtained and identified as an extension of recent results obtained by Ahmed, Grzadkowskia and Wudkab. The corresponding cosmology of models with regularized branes generated by such a 5D scalar field scenario is also investigated. It has been shown that the anisotropic evolution of the warp factor and consequently the Hubble like parameter are both driven by the radial coordinate on the brane, which leads to an emergent thick brane-world scenario with spherically symmetric time dependent warp factor. Meanwhile, the separability of variables depending on fifth dimension, y, which is exhibited by the equations of motion, allows one to recover the extra dimensional profiles obtained in the literature, namely the extra dimensional part of the scale (warp) factor and the scalar field dependence on y. Therefore, our results are mainly concerned with the time dependence of a spherically symmetric warp factor. Besides evincing possibilities for obtaining asymmetric stable brane-world scenarios, the extra dimensional profiles here obtained can also be reduced to those ones investigated in the literature.

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Alex E. Bernardini, R. T. Cavalcanti, Roldao da Rocha. 2014-11-13. Spherically Symmetric Thick Branes Cosmological Evolution. https://doi.org/10.1007/s10714-014-1840-x

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