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arXiv · hep-lat/0308022

Naturally Light Fermions from Dimensional Reduction

W. Bietenholz·A. Gfeller·U. -J. Wiese
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Abstract

We consider the 3-d Gross-Neveu model in the broken phase and construct a stable brane world by means of a domain wall and an anti-wall. Fermions of opposite chirality are localized on the walls and coupled through the 3-d bulk. At large wall separation βthe 2-d correlation length diverges exponentially, hence a 2-d observer cannot distinguish this situation from a 2-d space-time. The 3-d 4-fermion coupling and βfix the effective 2-d coupling such that the asymptotic freedom of the 2-d model arises. This mechanism provides criticality without fine tuning.

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W. Bietenholz, A. Gfeller, U. -J. Wiese. 2003-08-20. Naturally Light Fermions from Dimensional Reduction. https://doi.org/10.1016/s0920-5632(03)02737-3

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