Type IIB at eight derivatives: insights from Superstrings, Superfields and Superparticles

by Andreas Schachner (LMU Munich and Cornell University)

Monday 16 Dec 2024, 15:00 → 16:00 Europe/Rome

Aula Grassano

Completing the 10D Type II supergravity action at the eight-derivative level including RR-fields remains a central problem for string theory. In this talk, I report progress on the non-linear structure of Type IIB eight-derivative couplings involving the metric, the axio-dilaton and the complexified three-form $G_3$. I will argue that, at the level of five-point string amplitudes, the kinematics in the maximally R-symmetry-violating sector is fully matched by standard superspace integrals and by superparticle amplitudes in M-theory on a two-torus. The latter approach is used to verify its invariance under SL$(2,\mathbb{Z})$ duality. I further comment on the general structure of the higher-point kinematics for a subset of couplings.