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arXiv · hep-th/0407208

Brane solutions of a spherical sigma model in six dimensions

Hyun Min Lee·Antonios Papazoglou
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Abstract

We explore solutions of six dimensional gravity coupled to a non-linear sigma model, in the presence of co-dimension two branes. We investigate the compactifications induced by a spherical scalar manifold and analyze the conditions under which they are of finite volume and singularity free. We discuss the issue of single-valuedness of the scalar fields and provide some special embedding of the scalar manifold to the internal space which solves this problem. These brane solutions furnish some self-tuning features, however they do not provide a satisfactory explanation of the vanishing of the effective four dimensional cosmological constant. We discuss the properties of this model in relation with the self-tuning example based on a hyperbolic sigma model.

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Hyun Min Lee, Antonios Papazoglou. 2004-11-16. Brane solutions of a spherical sigma model in six dimensions. https://doi.org/10.1016/j.nuclphysb.2004.10.063

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