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arXiv · hep-th/9907041

World-Sheet Corrections Via D-Instantons

Edward Witten
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Abstract

We use a D-instanton or physical gauge approach to re-derive the heterotic string worldsheet instanton contribution to the superpotential in Calabi-Yau compactification. We derive an analogous formula for worldsheet instanton corrections to the moduli space metric in heterotic string or Type I compactification on a K3 surface. In addition, we give a global analysis of the phase of the worldsheet path integral of the heterotic string, showing precisely how the B-field must be interpreted.

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Edward Witten. 1999-07-07. World-Sheet Corrections Via D-Instantons. https://doi.org/10.1088/1126-6708%2F2000%2F02%2F030

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