Speaker: Francesco Riva
Title: Microscopic Bounds on Macroscopic Theories
Room: 3024
Zoom: https://zoom.us/j/186024391
Host: Markus Luty
Abstract: Effective Field Theories (EFTs) appear everywhere there is a mass scale. They serve to simplify complex multiscale problems, and as general tools to parametrise the unknown or incalculable (e.g. the pion chiral Lagrangian, gravity, or physics beyond the standard model - BSM). I will present how dispersion relations (both forward and at finite impact parameter) single out EFTs that originate from microscopic unitary theories, both at weak and at strong coupling. This reshapes the landscape of plausible physics BSM, and I will show that theories with very irrelevant interactions, theories with isolated massive higher-spin particles, and massive gravity don’t posses healthy UV completions.
