HEP Seminar: Justin Berman: "Positivity with Long–Range Interactions"

The 2->2 scattering amplitudes of unitary field theories obey positivity bounds that constrain, for example, Wilson coefficients in weakly-coupled effective field theories. However, theories with long range forces, namely electromagnetism and gravity, have IR divergences in 4 dimensions which make exclusive amplitudes ill-defined. In this talk, I will discuss how to recover positivity bounds in 4D by accounting for finite detector sizes and show that, in the weakly coupled limit, the bound is independent of experimental details other than the minimum detectable energy.

Justin Berman, PhD Student, University of Michigan

Host: Adrian Thompson

Add Event To My Group

Please sign-in