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Effective Actions Near Singularities: The STU-Model

Marco Zagermann
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Abstract

We derive the low energy effective action of the STU-model in four and five dimensions near the line T=U, where SU(2) gauge symmetry enhancement occurs. By `integrating in' the light W^{\pm} bosons together with their superpartners, the quantum corrected effective action becomes non-singular at T=U and manifestly SU(2) invariant. The four-dimensional theory is found to be consistent with modular invariance and the five-dimensional decompactification limit. This talk concisely summarizes results that have been obtained in collaboration with J. Louis and T. Mohaupt.

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Marco Zagermann. 2003-02-07. Effective Actions Near Singularities: The STU-Model. https://doi.org/10.1002/prop.200310113

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