# Galois currents and the projective kernel in Rational Conformal Field Theory

@article{Bantay2003GaloisCA, title={Galois currents and the projective kernel in Rational Conformal Field Theory}, author={Peter Bantay}, journal={arXiv: High Energy Physics - Theory}, year={2003} }

The notion of Galois currents in Rational Conformal Field Theory is introduced and illustrated on simple examples. This leads to a natural partition of all theories into two classes, depending on the existence of a non-trivial Galois current. As an application, the projective kernel of a RCFT, i.e. the set of all modular transformations represented by scalar multiples of the identity, is described in terms of a small set of easily computable invariants.

## 7 Citations

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We prove that the kernel of the natural action of the modular group on the center of the Drinfel'd double of a semisimple Hopf algebra is a congruence subgroup. To do this, we introduce a class of…

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