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arXiv · hep-th/9803129

Discrete symmetries of unitary minimal conformal theories

P. Ruelle·O. Verhoeven
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Abstract

We classify the possible discrete (finite) symmetries of two--dimensional critical models described by unitary minimal conformally invariant theories. We find that all but six models have the group Z_2 as maximal symmetry. Among the six exceptional theories, four have no symmetry at all, while the other two are the familiar critical and tricritical 3--Potts models, which both have an S_3 symmetry. These symmetries are the expected ones, and coincide with the automorphism groups of the Dynkin diagrams of simply--laced simple Lie algebras ADE. We note that extended chiral algebras, when present, are almost never preserved in the frustrated sectors.

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P. Ruelle, O. Verhoeven. 1998-03-16. Discrete symmetries of unitary minimal conformal theories. https://doi.org/10.1016/s0550-3213(98)00639-7

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