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Singular defects with fractional topological charge\\ in $σ$ models and gauge theories

A. R. Zhitnitsky
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Abstract

A novel class of self-dual solutions in $σ$ models and gauge theories is considered. The contribution of the corresponding fluctuations to the chiral condensate is calculated. We discuss the few tightly connected problems, such as the $U(1)$ problem, the $θ$ dependence and the chiral symmetry breaking within a framework of this approach. Arguments in favour of significance of the configurations with fractional topological charge are given.

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A. R. Zhitnitsky. 1993-11-30. Singular defects with fractional topological charge\\ in $σ$ models and gauge theories. https://doi.org/10.1016/0920-5632(94)90346-8

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