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arXiv · 2106.13820

Index-like Theorem for Massless Fermions in Spherically Symmetric Monopole Backgrounds

T. Daniel Brennan
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Abstract

In this paper we study massless fermions coupled to spherically symmetric $SU(N)$ monopoles without Yukawa couplings between the Higgs and fermion fields. The corresponding Dirac operator is not Fredholm and the associated eigenfunctions are not $L^2$-normalizable. Here we derive a formula for the dimension of the plane-wave normalizable kernel of such a Dirac operator for fermions of any representation of $SU(N)$ in the presence of any spherically symmetric monopole background. Notably, our results also apply to fermions coupled to monopoles that preserve non-abelian gauge symmetry.

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T. Daniel Brennan. 2021-06-25. Index-like Theorem for Massless Fermions in Spherically Symmetric Monopole Backgrounds. https://doi.org/10.1007/jhep03(2022)095

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