Microcausality and positivity without Lorentz invariance

by Alessandro Podo (IHES, Paris)

Tuesday 18 Feb 2025, 14:00 → 15:30 Europe/Rome

Aula Conversi (Dip. di Fisica - Edificio G. Marconi)

I will describe how causality implies certain non-perturbative analyticity and exponential boundedness conditions on correlators of relativistic QFTs, in a mixed (t,k) representation. I will then discuss their implications for correlators in Lorentz-breaking backgrounds, including finite-density states and curved spacetimes, and show how they can be used to derive positivity bounds on inflationary theories. Along the way, I will compare with the case of S-matrix positivity in flat space Lorentz-invariant theories.

Zoom link: https://uniroma1.zoom.us/j/87038625161?pwd=cEtGRjZNT2VWSlJIWmxaYmxSMDhRZz09