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arXiv · hep-th/9307158

Topological Amplitudes in String Theory

I. Antoniadis·E. Gava·K. S. Narain·T. R. Taylor
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Abstract

We show that certain type II string amplitudes at genus $g$ are given by the topological partition function $F_g$ discussed recently by Bershadsky, Cecotti, Ooguri and Vafa. These amplitudes give rise to a term in the four-dimensional effective action of the form $\sum_g F_g W^{2g}$, where $W$ is the chiral superfield of $N=2$ supergravitational multiplet. The holomorphic anomaly of $F_g$ is related to non-localities of the effective action due to the propagation of massless states. This result generalizes the holomorphic anomaly of the one loop case which is known to lead to non-harmonic gravitational couplings.

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I. Antoniadis, E. Gava, K. S. Narain, T. R. Taylor. 1993-07-26. Topological Amplitudes in String Theory. https://doi.org/10.1016/0550-3213(94)90617-3

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