Causality Sum Rules in Quantum Field Theory
In effective field theory, causality fixes the signs of certain interactions. I will describe how these Lorentzian constraints are encoded in the Euclidean theory, and use the conformal bootstrap to derive analogous causality constraints in CFT. The result is a position-space analogue of dispersion relations and the optical theorem. Applied to spinning fields, these constraints include the Hofman-Maldacena bounds derived from conformal collider physics. I will also discuss applications to holographic theories and non-conformal effective field theory.
For help, please contact James Tuan.