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arXiv · hep-th/9811100

On conformal field theories at fractional levels

Ernest Baver·Doron Gepner·Umut Gursoy
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Abstract

For each lattice one can define a free boson theory propagating on the corresponding torus. We give an alternative definition where one employs any automorphism of the group $M^*/M$. This gives a wealth of conformal data, which we realize as some bosonic theory, in all the `regular' cases. We discuss the generalization to affine theories. As a byproduct, we compute the gauss sum for any lattice and any diagonal automorphism.

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Ernest Baver, Doron Gepner, Umut Gursoy. 1998-11-11. On conformal field theories at fractional levels. https://doi.org/10.1016/s0550-3213(99)00356-9

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