Superstring amplitudes and the associator

  • J. M. DrummondEmail author
  • E. Ragoucy
Open Access


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.


Scattering Amplitudes Brane Dynamics in Gauge Theories 


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Copyright information

© SISSA 2013

Authors and Affiliations

  1. 1.PH-TH, CERN, Case C01600Geneva 23Switzerland
  2. 2.LAPTH, Université de Savoie, CNRSAnnecy-le-Vieux CedexFrance

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