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arXiv · hep-th/0301125

Effective Actions near Singularities

Jan Louis·Thomas Mohaupt·Marco Zagermann
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Abstract

We study the heterotic string compactified on K3 x T^2 near the line T=U, where the effective action becomes singular due to an SU(2) gauge symmetry enhancement. By `integrating in' the light W^\pm vector multiplets we derive a quantum corrected effective action which is manifestly SU(2) invariant and non-singular. This effective action is found to be consistent with a residual SL(2,Z) quantum symmetry on the line T=U. In an appropriate decompactification limit, we recover the known SU(2) invariant action in five dimensions.

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Jan Louis, Thomas Mohaupt, Marco Zagermann. 2003-04-24. Effective Actions near Singularities. https://doi.org/10.1088/1126-6708%2F2003%2F02%2F053

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