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Fusion rules of modular invariants

David E Evans
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Abstract

Modular invariants satisfy remarkable fusion rules. Let $Z$ be a modular invariant associated to a braided subfactor $N\subset M$. The decomposition of the non-normalized modular invariants $Z Z^{*}$ and $Z^{*}Z$ into sums of normalized modular invariants is related to the decomposition of the full induced $M-M$ system of sectors.

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David E Evans. 2002-04-23. Fusion rules of modular invariants. https://doi.org/10.1142/s0129055x02001351

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