3 problems

Let $\rho,\sigma$ be permutations in the symmetric group $\mathfrak S_k$, and let $J_{\rho,\sigma}(\mathbf a,\mathbf b,\mathbf c)$ be the corresponding multiple complex integral. A…

Genus-one closed string amplitudes have low-energy expansions involving modular graph functions and forms. The single-valued map is defined on iterated integrals of modular forms.…

The low-energy expansion of open string amplitudes is expressed in terms of multiple zeta values, while closed string amplitudes at tree level involve single-valued multiple zeta v…