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Gravitating global monopoles in extra dimensions and the brane world concept

K. A. Bronnikov·B. E. Meierovich
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Abstract

Multidimensional configurations with Minkowski external space-time and a spherical global monopole in extra dimensions are discussed in the context of the brane world concept. The monopole is formed with a hedgehog-like set of scalar fields ϕ^i with a symmetry-breaking potential V depending on the magnitude ϕ^2 = ϕ^i ϕ^i. All possible kinds of globally regular configurations are singled out without specifying the shape of V(ϕ). These variants are governed by the maximum value ϕ_m of the scalar field, characterizing the energy scale of symmetry breaking. If ϕ_m < ϕ_cr (where ϕ_cr is a critical value of ϕrelated to the multidimensional Planck scale), the monopole reaches infinite radii while in the ``strong field regime'', when ϕ_m\geq ϕ_cr, the monopole may end with a cylinder of finite radius or possess two regular centers. The warp factors of monopoles with both infinite and finite radii may either exponentially grow or tend to finite constant values far from the center. All such configurations are shown to be able to trap test scalar matter, in striking contrast to RS2 type 5D models. The monopole structures obtained analytically are also found numerically for the Mexican hat potential with an additional parameter acting as a cosmological constant.

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K. A. Bronnikov, B. E. Meierovich. 2005-07-07. Gravitating global monopoles in extra dimensions and the brane world concept. https://doi.org/10.1134/1.2163920

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