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arXiv · hep-th/9412009

Quasi-Galois Symmetries of the Modular S-Matrix

J. Fuchs·A. N. Schellekens·C. Schweigert
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Abstract

The recently introduced Galois symmetries of RCFT are generalized, for the WZW case, to `quasi-Galois symmetries'. These symmetries can be used to derive a large number of equalities and sum rules for entries of the modular matrix S, including some that previously had been observed empirically. In addition, quasi-Galois symmetries allow to construct modular invariants and to relate S-matrices as well as modular invariants at different levels. They also lead us to an extremely plausible conjecture for the branching rules of the conformal embeddings of g into so(dim g).

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J. Fuchs, A. N. Schellekens, C. Schweigert. 1994-12-01. Quasi-Galois Symmetries of the Modular S-Matrix. https://doi.org/10.1007/bf02099557

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