“Bootstrapping String Amplitudes”
In this talk, I will ask a bedrock question of quantum gravity: Is string theory unique? String amplitudes famously accomplish several extraordinary and interrelated mathematical feats, including an infinite spin tower, tame UV behavior, and dual resonance. However, this is not enough to uniquely fix the theory, and it is possible to construct infinite new classes of tree-level, dual resonant amplitudes. These constructions can be strongly constrained using multiparticle factorization. Beyond four point, the evaluation of tree-level string amplitudes themselves at arbitrary kinematics is an unsolved problem, which I will solve for five-point scattering in this talk, as well as outline the proof of dual resonance at n-point. Furthermore, I will identify mathematical criteria for the S-matrix from which string amplitudes—including their spectra—can be uniquely bootstrapped.
Host: David Poland