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arXiv · hep-th/9203071

Moduli Corrections to Gravitational Couplings from String loops

I. Antoniadis·E. Gava·K. S. Narain
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Abstract

We study moduli dependent threshold corrections to gravitational couplings in the case of the heterotic string compactified on a symmetric orbifold, for untwisted moduli, extending previous analysis on gauge couplings. Like in the gauge case, the contribution comes entirely from the spacetime $N=2$ sector. As a byproduct, this calculation provides a simple derivation of the trace anomaly coefficients for the different fields coupled to gravity.

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I. Antoniadis, E. Gava, K. S. Narain. 1992-03-25. Moduli Corrections to Gravitational Couplings from String loops. https://doi.org/10.1016/0370-2693(92)90009-s

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