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arXiv · hep-th/9912285

Dimensional reduction, magnetic flux strings, and domain walls

C. D. Fosco·A. Lopez·F. A. Schaposnik
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Abstract

We study some consequences of dimensionally reducing systems with massless fermions and Abelian gauge fields from 3+1 to 2+1 dimensions. We first consider fermions in the presence of an external Abelian gauge field. In the reduced theory, obtained by compactifying one of the coordinates `a la Kaluza-Klein, magnetic flux strings are mapped into domain wall defects. Fermionic zero modes, localized around the flux strings of the 3+1 dimensional theory, become also zero modes in the reduced theory, via the Callan and Harvey mechanism, and are concentrated around the domain wall defects. We also study a dynamical model: massless $QED_4$, with fermions confined to a plane, deriving the effective action that describes the `planar' system.

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C. D. Fosco, A. Lopez, F. A. Schaposnik. 1999-12-31. Dimensional reduction, magnetic flux strings, and domain walls. https://doi.org/10.1016/s0550-3213(00)00315-1

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