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arXiv · hep-th/9912283

A Heavy Fermion Can Create a Soliton: A 1+1 Dimensional Example

E. Farhi·N. Graham·R. L. Jaffe·H. Weigel
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Abstract

We show that quantum effects can stabilize a soliton in a model with no soliton at the classical level. The model has a scalar field chirally coupled to a fermion in 1+1 dimensions. We use a formalism that allows us to calculate the exact one loop fermion contribution to the effective energy for a spatially varying scalar background. This energy includes the contribution from counterterms fixed in the perturbative sector of the theory. The resulting energy is therefore finite and unambiguous. A variational search then yields a fermion number one configuration whose energy is below that of a single free fermion.

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E. Farhi, N. Graham, R. L. Jaffe, H. Weigel. 2000-03-27. A Heavy Fermion Can Create a Soliton: A 1+1 Dimensional Example. https://doi.org/10.1016/s0370-2693(00)00108-8

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