Chaotic many-body quantum dynamics, spectral correlations, and energy diffusion

by John Chalker (Oxford)

Thursday 11 Jun 2026, 16:15 → 18:15 Europe/Berlin

For almost a century, much of the effort studying many-body quantum systems has focussed on behaviour at low temperature, or in solvable models with many conserved quantities. Recently, minimal models have been developed which give a window onto dynamics in generic systems, unrestricted by temperature or conservation laws. These models make it possible to explore the main features expected in chaotic many-body dynamics using quite simple analytical calculations. This is progress that I think goes far beyond what could reasonably have been dreamed of ten years ago, but it is built on foundations laid in the 1950s.

After giving a short introduction to these general developments, I will describe a study of chaotic many-body quantum dynamics in a minimal model with spatial structure and local interactions, which is analytically tractable in a suitable limit. In this limit we show that energy dynamics is described by a classical master equation and is diffusive. We also show that the spectral form factor, which characterises correlations between energy eigenvalues, can be expressed exactly in terms of the solution to this master equation.  [Joint work with Dominik Hahn, arXiv2510.02198]