I will present a recent extension of the Veneziano and Shapiro-Virasoro amplitudes with arbitrarily excited strings (AES) in critical bosonic string theory. I will also discuss several novel applications, such as chaotic signatures in string amplitudes with excited states, the absorption universality emerging from the cross section of AES and the emission rate of AES with particular focus on the photon and graviton emission spectrum. Finally I will comment on the spin multipole expansion and the (classical) infinite spin limit of three-point Heavy-Light-Heavy string amplitudes for leading and sub-leading Regge trajectories.

Biography

Maurizio Firrotta is currently a postdoctoral researcher at Fudan University in Shanghai since autumn 2025. Previously, he obtained the Marie Skłodowska-Curie Fellowship with a project focused on the chaotic aspects of black holes in string theory, hosted at the Crete Center for Theoretical Physics (CCTP) from 2023 to 2025. From 2021 to 2022, he was visiting research collaborator at the University of Rome "Tor Vergata." He received his PhD in spring 2021 and his MSc in spring 2017 from University of Rome "Tor Vergata." His research focuses on scattering processes in quantum gravity and related chaotic aspects.

Inviter: Matti Jarvinen