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arXiv:2503.07727 · Journal of Mathematical Physics

Decomposition in 2d non-invertible gaugings

Alonso Perez-Lona

Published Feb 1, 2026• 0 citations
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Abstract

We extend the decomposition conjecture to 2d quantum field theories with a gauged Rep(H) symmetry category for H a finite-dimensional semisimple Hopf algebra with Rep(G) trivially-acting and Vec(Γ) the remaining symmetry, for G, Γ finite groups. We check our extension by explicitly computing partition functions, and by verifying that previous results arise as special cases. Furthermore, we compute the topological operators responsible for enforcing the decomposition. Then, drawing from these results, we formulate a plausible decomposition conjecture for the even more general case of Rep(H″) trivially-acting and Rep(H′) the remaining symmetry, for H′, H″ Hopf algebras, not necessarily associated with groups.

DOI
10.1063/5.0283628

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We extend the decomposition conjecture to 2d quantum field theories with a gauged Rep(H) symmetry category for H a finite-dimensional semisimple Hopf algebra with Rep(G) trivially-acting and Vec(Γ) the remaining symmetry, for G, Γ finite groups. We check our extension by explicitly computing partition functions, and by verifying that previous results arise as special cases. Furthermore, we compute the topological operators responsible for enforcing the decomposition. Then, drawing from these results, we formulate a plausible decomposition conjecture for the even more general case of Rep(H″) trivially-acting and Rep(H′) the remaining symmetry, for H′, H″ Hopf algebras, not necessarily associated with groups.
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