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arXiv · 1809.03681

Relaxation to gaussian and generalized Gibbs states in systems of particles with quadratic hamiltonians

Chaitanya Murthy·Mark Srednicki
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Abstract

We present an elementary, general, and semi-quantitative description of relaxation to gaussian and generalized Gibbs states in lattice models of fermions or bosons with quadratic hamiltonians. Our arguments apply to arbitrary initial states that satisfy a mild condition on clustering of correlations. We also show that similar arguments can be used to understand relaxation (or its absence) in systems with time-dependent quadratic hamiltonians, and provide a semi-quantitative description of relaxation in quadratic periodically driven (Floquet) systems.

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Chaitanya Murthy, Mark Srednicki. 2018-09-11. Relaxation to gaussian and generalized Gibbs states in systems of particles with quadratic hamiltonians. https://doi.org/10.1103/physreve.100.012146

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