title: Approach to typicality in many-body quantum systems.
abstract: The recent discovery that for large Hilbert spaces, almost all (that is, typical) Hamiltonians have eigenstates that place small subsystems in thermal equilibrium, has shed much light on the origins of irreversibility and thermalization. Here we give numerical evidence that many-body lattice systems generically approach typicality as the number of subsystems is increased, and thus provide further support for the eigenstate thermalization hypothesis. Our results indicate that the deviation of many-body systems from typicality decreases exponentially with the number of systems. Further, by averaging over a number of randomly selected nearest-neighbor interactions, we obtain a powerlaw for the atypicality as a function of the Hilbert space dimension, distinct from the power law possessed by random Hamiltonians.
authors.affiliation: Department of Physics, University of Massachusetts at Boston, 100 Morrissey Boulevard, Boston, Massachusetts 02125, USA.
authors.forename: Shawn
authors.initials: S
authors.lastname: Dubey
authors.forename: Luciano
authors.initials: L
authors.lastname: Silvestri
authors.forename: Justin
authors.initials: J
authors.lastname: Finn
authors.forename: Sai
authors.initials: S
authors.lastname: Vinjanampathy
authors.forename: Kurt
authors.initials: K
authors.lastname: Jacobs
mesh_terms: D003198:Computer Simulation; D008956:Models, Chemical; D008958:Models, Molecular; D011789:Quantum Theory; D013816:Thermodynamics