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Generalised discrete torsion and mirror symmetry for G_2 manifolds

Matthias R. Gaberdiel·Peter Kaste
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Abstract

A generalisation of discrete torsion is introduced in which different discrete torsion phases are considered for the different fixed points or twist fields of a twisted sector. The constraints that arise from modular invariance are analysed carefully. As an application we show how all the different resolutions of the T^7/Z_2^3 orbifold of Joyce have an interpretation in terms of such generalised discrete torsion orbifolds. Furthermore, we show that these manifolds are pairwise identified under G_2 mirror symmetry. From a conformal field theory point of view, this mirror symmetry arises from an automorphism of the extended chiral algebra of the G_2 compactification.

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Matthias R. Gaberdiel, Peter Kaste. 2004-08-09. Generalised discrete torsion and mirror symmetry for G_2 manifolds. https://doi.org/10.1088/1126-6708%2F2004%2F08%2F001

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