Pure state equilibration and dynamical correlation functions

In this talk we aim to shed light on the process of pure state equilibration in a large class of quantum many body systems. First this topic is approached by studying two point correlation functions, which model time evolution for systems after weak pertubations away from equilibrium. This reveals that under general assumptions, these correlation functions factorize in late time proving dissiptation emerges from unitary dynamics. An upper bound on the timescale for equilibration in autocorrelations is derived, and numerically investigated. Then, revisting the work from Srednicki (J. Phys. A 32 (1999) 1163) we link this work to the problem of pure state equilibration. We provide arguments that constrain the initial behavior of the equilibration after generic quantum quenches. These constraints are verified through extensive numerical simulations.