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arXiv · hep-th/9910056

The low energy expansion of the one-loop type II superstring amplitude

Michael B. Green·Pierre Vanhove
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Abstract

The one-loop four-graviton amplitude in either of the type II superstring theories is expanded in powers of the external momenta up to and including terms of order s^4 log s R^4, where R^4 denotes a specific contraction of four linearized Weyl tensors and s is a Mandelstam invariant. Terms in this series are obtained by integrating powers of the two-dimensional scalar field theory propagator over the toroidal world-sheet as well as the moduli of the torus. The values of these coefficients match expectations based on duality relations between string theory and eleven-dimensional supergravity.

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Michael B. Green, Pierre Vanhove. 1999-11-01. The low energy expansion of the one-loop type II superstring amplitude. https://doi.org/10.1103/physrevd.61.104011

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