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arXiv · 2412.21107

Coupled minimal models revisited II: Constraints from permutation symmetry

António Antunes·Connor Behan
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Abstract

Coupling $N$ large $m$ minimal models and flowing to IR fixed points is a systematic way to build new classes of compact unitary 2d CFTs which are likely to be irrational, and potentially have a positive Virasoro twist gap above the vaccuum. In this paper, we build on the construction of [1], establishing that, for spins less than 10, additional currents transforming in non-trivial irreducible representations of the permutation symmetry $S_N$ are not conserved at the IR fixed points. Along the way, we develop a finer understanding of the spectrum of these theories, of the special properties of the $N=4$ case and of non-invertible symmetries that constrain them. We also discuss variations of the original setup of [1] some of which can exist for smaller values of the UV central charge.

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António Antunes, Connor Behan. 2024-12-30. Coupled minimal models revisited II: Constraints from permutation symmetry. https://doi.org/10.21468/scipostphys.18.4.132

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