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arXiv · 1304.7267

Polylogarithms, Multiple Zeta Values and Superstring Amplitudes

Johannes Broedel·Oliver Schlotterer·Stephan Stieberger
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Abstract

A formalism is provided to calculate tree amplitudes in open superstring theory for any multiplicity at any order in the inverse string tension. We point out that the underlying world-sheet disk integrals share substantial properties with color-ordered tree amplitudes in Yang-Mills field theories. In particular, we closely relate world-sheet integrands of open-string tree amplitudes to the Kawai-Lewellen-Tye representation of supergravity amplitudes. This correspondence helps to reduce the singular parts of world-sheet disk integrals -including their string corrections- to lower-point results. The remaining regular parts are systematically addressed by polylogarithm manipulations.

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Johannes Broedel, Oliver Schlotterer, Stephan Stieberger. 2013-07-16. Polylogarithms, Multiple Zeta Values and Superstring Amplitudes. https://doi.org/10.1002/prop.201300019

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