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arXiv · hep-th/0412280

Generalised $G_2$-structures and type IIB superstrings

Claus Jeschek·Frederik Witt
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Abstract

The recent mathematical literature introduces generalised geometries which are defined by a reduction from the structure group $SO(d,d)$ of the vector bundle $T^d\oplus T^{d*}$ to a special subgroup. In this article we show that compactification of IIB superstring vacua on 7-manifolds with two covariantly constant spinors leads to a generalised $G_2$-structure associated with a reduction from SO(7,7) to $G_2\times G_2$. We also consider compactifications on 6-manifolds where analogously we obtain a generalised SU(3)-structure associated with $SU(3)\times SU(3)$, and show how these relate to generalised $G_2$-structures.

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Claus Jeschek, Frederik Witt. 2005-03-31. Generalised $G_2$-structures and type IIB superstrings. https://doi.org/10.1088/1126-6708%2F2005%2F03%2F053

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