Hydrodynamics from Microscopics

by Mark Mezei (University of Oxford)

Wednesday 23 Sept 2026, 14:00 → 16:00 Europe/Zurich

4/3-006 - TH Conference Room (CERN)

This talk is part of QFT constraints on non-equilibrium phenomena

Like the plasma created in heavy ion collisions, strongly interacting systems at large energy density tend to behave like a liquid. Their long-lived excitations are associated with long wavelength energy excesses, and these are governed by hydrodynamics as an effective field theory (EFT). Can we derive this EFT from the microscopic Lagrangian? In this talk, we show how the EFT of energy diffusion can be derived in the solvable chaotic many-body model, the SYK lattice. We compute the hydrodynamic effective action to high orders in the derivative expansion, determine all the corresponding transport coefficients, and discuss its symmetries. We outline how this framework extends to the computation of probes of quantum information scrambling and entanglement dynamics using a fourfold complex time contour. 

Recording