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arXiv · 1304.7304

All order alpha'-expansion of superstring trees from the Drinfeld associator

Johannes Broedel·Oliver Schlotterer·Stephan Stieberger·Tomohide Terasoma
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Abstract

We derive a recursive formula for the alpha'-expansion of superstring tree amplitudes involving any number N of massless open string states. String corrections to Yang-Mills field theory are shown to enter through the Drinfeld associator, a generating series for multiple zeta values. Our results apply for any number of spacetime dimensions or supersymmetries and chosen helicity configurations.

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Johannes Broedel, Oliver Schlotterer, Stephan Stieberger, Tomohide Terasoma. 2014-02-17. All order alpha'-expansion of superstring trees from the Drinfeld associator. https://doi.org/10.1103/physrevd.89.066014

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