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arXiv · 1403.2410

On symmetries of N=(4,4) sigma models on T^4

Roberto Volpato
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Abstract

Motivated by an analogous result for K3 models, we classify all groups of symmetries of non-linear sigma models on a torus T^4 that preserve the N=(4,4) superconformal algebra. The resulting symmetry groups are isomorphic to certain subgroups of the Weyl group of E8, that plays a role similar to the Conway group for the case of K3 models. Our analysis heavily relies on the triality automorphism of the T-duality group SO(4,4,Z). As a byproduct of our results, we discover new explicit descriptions of K3 models as asymmetric orbifolds of torus CFTs.

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Roberto Volpato. 2014-08-08. On symmetries of N=(4,4) sigma models on T^4. https://doi.org/10.1007/jhep08(2014)094

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