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arXiv · hep-th/9908034

Domain walls and dimensional reduction

C. D. Fosco·R. C. Trinchero
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Abstract

We study some properties of a dimensional reduction mechanism for fermions in an odd number D+1 of spacetime dimensions. A fermionic field is equipped with a mass term with domain wall like defects along one of the spacelike dimensions, which is moreover compactified. We show that there is a regime such that the only relevant degrees of freedom are massless fermionic fields in D dimensions. For any fixed gauge field configuration, the extra modes may be decoupled, since they can be made arbitrarily heavy. This decoupling combines the usual Kaluza-Klein one, due to the compactification, with a mass enhancement for the non-zero modes provided by the domain wall mechanism. We obtain quantitative results on the contribution of the massive modes in the cases D=2 and D=4.

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C. D. Fosco, R. C. Trinchero. 1999-08-04. Domain walls and dimensional reduction. https://doi.org/10.1016/s0550-3213(99)00591-x

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