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arXiv · 2406.15552

The Monopole-Fermion Problem in a Chiral Gauge Theory (the $\psi\chi\eta$ Model)

Stefano Bolognesi·Bruno Bucciotti·Andrea Luzio
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Abstract

The scattering of electrically charged fermions on magnetic monopole leads to the Callan-Rubakov problem. We discuss some aspects of this problem for Abelian gauge theories with chiral fermions in a Dirac monopole background. In some cases, it is possible to embed the theory in a non-Abelian gauge theory where the monopole is regularized as a 't Hooft-Polyakov monopole. One theory of this kind is the $SU(N)$ chiral gauge theory with fermions in the symmetric, anti-antisymmetric and anti-fundamental representations also called "$\psi \chi \eta$" model, with an extra adjoint scalar that induces the Abelianization of the gauge group. We examine this model in detail and provide a possible solution for the condensates around the monopole, the symmetry preserving boundary conditions, and discuss the particle scattering problem.

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Stefano Bolognesi, Bruno Bucciotti, Andrea Luzio. 2024-06-21. The Monopole-Fermion Problem in a Chiral Gauge Theory (the $\psi\chi\eta$ Model). https://arxiv.org/abs/2406.15552

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