Effective Actions near Singularities
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چکیده
We study the heterotic string compactified on K3× 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± 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. January 2003 Work supported by: DFG – The German Science Foundation, GIF – the German–Israeli Foundation for Scientific Research, European RTN Program HPRN-CT-2000-00148 and the DAAD – the German Academic Exchange Service.
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تاریخ انتشار 2003