Joint Theory Seminar: Simon Caron-Huot

Title: Asymptotic measurements and crossing

Abstract: Why are scattering amplitudes analytic?  I will argue that, in addition to the familiar crossing relations that interchange particles and antiparticles, analyticity relates observables within a much broader family.  These generalize conventional scattering amplitudes by changing the operator ordering, and arise naturally when trying to explain analyticity from causality: the vanishing of spacelike commutators.  I will discuss applications to in-in expectation values of physical interest. Based on 2308.02125 and 2310.12199.