Motivic Multiple Zeta Values and Superstring Amplitudes

Understand

The structure of tree-level open and closed superstring amplitudes is analyzed.

• For the open superstring amplitude we find a striking and elegant form, which allows to disentangle its alpha'-expansion into several contributions accounting for different classes of multiple zeta values.
• This form is bolstered by the decomposition of motivic multiple zeta values, i.e.
• the latter encapsulate the alpha'-expansion of the superstring amplitude.