Bounds on transport from univalence and pole-skipping

Understand

Bounds on transport represent a way of understanding allowable regimes of quantum and classical dynamics.

• Numerous such bounds have been proposed, either for classes of theories or (by using general arguments) universally for all theories.
• Few are exact and inviolable.
• I present a new set of methods and sufficient conditions for deriving exact, rigorous, and sharp bounds on all coefficients of hydrodynamic dispersion relations, including diffusivity and the speed of sound.