Codimension-Two Defects and SYM on Orbifolds

Roman Mauch; Lorenzo Ruggeri

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arXiv · 2502.13611

Codimension-Two Defects and SYM on Orbifolds

Roman Mauch·Lorenzo Ruggeri

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Abstract

We study $U(N)$ SYM theories on spaces with orbifold singularities via an equivalent description in terms of gauge theories on smooth manifolds with insertions of Gukov-Witten and twist defects. The combined effect of the defects is to render the fields multivalued with respect to rotations around the support of the defects. This motivates a relation with theories on branched covers, for which the multivaluedness has a geometric interpretation. We compute the partition function of the theory with defects on a patch and use it as a building block to compute partition functions on several closed spaces with conical singularities.

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Roman Mauch, Lorenzo Ruggeri. 2025-02-19. Codimension-Two Defects and SYM on Orbifolds. https://arxiv.org/abs/2502.13611

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