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arXiv · hep-th/9610009

Fermion Bags in the Massive Gross-Neveu Model

J. Feinberg·A. Zee
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Abstract

As has long been known, it is energetically favorable for massive fermions to deform the homogeneous vacuum around them, giving rise to extended bag-like objects. We study this phenomenon non-perturbatively in a model field theory, the $1+1$ dimensional Massive Gross-Neveu model, in the large $N$ limit. We prove that the bags in this model are necessarily time dependent. We calculate their masses variationally and demonstrate their stability. We find a non-analytic behavior in these masses as we approach the standard massless Gross-Neveu model and argue that this behavior is caused by the kink-antikink threshold. This work extends our previous work to a non-integrable field theory.

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J. Feinberg, A. Zee. 1996-10-02. Fermion Bags in the Massive Gross-Neveu Model. https://doi.org/10.1016/s0370-2693(97)00993-3

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