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arXiv · 1301.0794

Superstring amplitudes and the associator

J. M. Drummond·E. Ragoucy
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Abstract

We investigate a pattern in the $α'$ expansion of tree-level open superstring amplitudes which correlates the appearance of higher depth multiple zeta values with that of simple zeta values in a particular way. We rephrase this relationship in terms of the coaction on motivic multiple zeta values and show that the pattern takes a very simple form, which can be simply explained by relating the amplitudes to the Drinfel'd associator derived from the Knizhnik-Zamolodchikov equation. Given this correspondence we show that, at least in the simplest case of the four-point amplitude, the associator can be used to extract the form of the amplitude.

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J. M. Drummond, E. Ragoucy. 2013-01-04. Superstring amplitudes and the associator. https://doi.org/10.1007/jhep08(2013)135

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