Speaker
Description
Understanding how highly-occupied quantum fields equilibrate is a central challenge in nonequilibrium quantum field theory, with direct relevance to the pre-equilibrium dynamics of relativistic heavy-ion collisions and the reheating epoch of the early Universe. Classical-statistical approaches capture the large-occupancy regime but cannot describe genuine quantum equilibration. Here we show that this problem is naturally amenable to quantum computation and perform first quantum simulations of particle production from classical fields in lattice λφ⁴ theory. Using coherent states as initial conditions, we find that particle production is accompanied by the equilibration of observables, which persists for timescales several times longer than the initial equilibration time before quantum Poincaré recurrences set in. Our results establish a first-principles route toward nonequilibrium quantum field theory on quantum computers and provide insight into the emergence of equilibrated states in isolated systems.
