Kick-off event: AI and the future of mathematics and physics - 21.10.2026
In light of recent developments, the incoming kick-off event at the Institut Henri Poincaré will take the form of a debate gathering mathematicians and theoretical physicists around the role of AI in the practice of research. More information will come soon.
Scattering amplitude of closed strings at genus one
byMehregan Doroudiani
Abstract:Perturbative calculations of string amplitudes are twofold: an expansion in the string coupling (the genus expansion of the worldsheet) and a low-energy expansion in the momenta. In this talk, I will focus on the low-energy expansion of closed string amplitudes at genus one, specifically for four- and five-point massless states of type IIB superstrings in flat spacetime. Evaluating these amplitudes involves integrating over the moduli space of punctured tori. I will demonstrate how the formalism of equivariant iterated Eisenstein integrals can be used to systematically calculate these integrals. Additionally, I will discuss the implications of these results for the S-duality of type IIB and conclude by exploring the underlying number-theoretic aspects of string amplitudes.