Mean values of current operators in integrable models

by Balazs Poszgay (Budapest University of Technology and Economics (BME))

Monday 7 Oct 2019, 14:00 → 15:00 Europe/Zurich

4/2-037 - TH meeting room (CERN)

Abstract:
Quantum integrable models are special many body systems: they possess an infinite family of conserved charges, that constrain the dynamical processes and forbid the decay of quasi-particle excitations. As an effect, these systems exhibit ballistic transport, which can be
described by the recent theory of Generalized Hydrodynamics (GHD). One of the cornerstones of GHD is the exact knowledge of the mean values of the currents associated to the conserved charges. We present an exact result for the current mean values, valid in arbitrary finite volume and also the thermodynamic limit. We explain that the exact quantum result agrees with a simple semi-classical computation. Thus
we observe an exact quantum-classical correspondence. This is possible because the exact wave functions of the integrable models are two-particle reducible for any interaction strength.