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arXiv · hep-th/0111050

D-brane probes on G2 Orbifolds

G. Ferretti·P. Salomonson·D. Tsimpis
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Abstract

We consider type IIB string theory on a seven dimensional orbifold with holonomy in G2. The motivation is to use D1-branes as probes of the geometry. The low energy theory on the D1-brane is a sigma-model with two real supercharges (N = (1,1) in two dimensional language). We study in detail the closed and open string sectors and propose a coupling of the twisted fields to the brane that modifies the vacuum moduli space so that the singularity at the origin is removed. Instead of coming from D-terms, which are not present here, the modification comes from a ``twisted'' mass term for the seven scalar multiplets on the brane. The proposed mechanism involves a generalization of the moment map.

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G. Ferretti, P. Salomonson, D. Tsimpis. 2002-01-30. D-brane probes on G2 Orbifolds. https://doi.org/10.1088/1126-6708%2F2002%2F03%2F004

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