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On new gravitational instantons describing creation of brane-worlds

M. Bouhmadi-Lopez·P. F. Gonzalez-Diaz·A. Zhuk
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Abstract

By considering 5--dimensional cosmological models with a bulk filled with a pressureless scalar field; equivalently dust matter, and a negative cosmological constant, we have found a regular instantonic solution which is free from any singularity at the origin of the extra--coordinate. This instanton describes 5--dimensional asymptotically anti de Sitter wormhole, when the bulk has a topology R times S^4. Compactified brane-world instantons which are built up from such instantonic solution describe either a single brane or a string of branes. Their analytical continuation to the pseudo--Riemannian metric can give rise to either 4-dimensional inflating branes or solutions with the same dynamical behaviour for extra--dimension and branes, in addition to multitemporal solutions. Dust brane-world models with arbitrary dimensions (D >= 5) as well as other spatial topologies are also briefly discussed.

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M. Bouhmadi-Lopez, P. F. Gonzalez-Diaz, A. Zhuk. 2002-08-30. On new gravitational instantons describing creation of brane-worlds. https://doi.org/10.1088/0264-9381%2F19%2F19%2F306

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