Fisica Matematica Equilibration in one-dimensional quantum hydrodynamic systems Spyros Sotiriadis
17-02-2017 - 10:00 AULA 211 - Largo San Leonardo Murialdo,1 - Roma We study quench dynamics and equilibration in one-dimensional quantum hydrodynamics, which provides effective descriptions of the density and velocity fields in
gapless quantum gases. We show that the information content of the large time steady state is inherently connected to the presence of ballistically moving localised
excitations. When such excitations are present, the system retains memory of all initial correlations up to infinite times, thus evading decoherence. We demonstrate
this connection in the context of the quantum KdV equation, which admits a hybrid representation in terms of bosonised and fermionised fields. When either dispersion
or interaction is present, initially localised excitations spread with time and the steady state is Gaussian in terms of the bosonised or fermionised field
respectively. When both dispersion and interaction are simultaneously present, localisation can be induced by the formation of solitary waves, whose stability at the
quantum level remains however an open theoretical problem. org: GIULIANI Alessandro
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