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arXiv:2204.06463 · SciPost Physics

Equal-time approach to real-time dynamics of quantum fields

R.J. Ott, Torsten V. Zache, Jürgen Berges

Published Feb 1, 2023• 2 citations
arXivHTMLPDF

Abstract

We employ the equal-time formulation of quantum field theory to derive effective kinetic theories, first for a weakly coupled non-relativistic Bose gas, and then for a strongly correlated system of self-interacting N N -component fields. Our results provide the link between state-of-the-art measurements of equal-time effective actions using quantum simulator platforms, as employed in [Phys. Rev. X 10, 011020 (2020); Nat. Phys. 16, 1012 (2020)], and observables underlying effective kinetic or hydrodynamic descriptions. New non-perturbative approximation schemes can be developed and certified this way, where the a priori time-local formulation of the equal-time effective action has crucial advantages over the conventional closed-time-path approach which is non-local in time.

DOI
10.21468/scipostphys.14.2.011

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