SciPost Physics

SciPost Phys. 4, 008 (2018) · published 31 January 2018

• doi: 10.21468/SciPostPhys.4.1.008
• pdf
• BiBTeX
• RIS
• Submissions/Reports
• 

Abstract

We unveil the universal (model-independent) symmetry satisfied by Schwinger-Keldysh quantum field theories whenever they describe equilibrium dynamics. This is made possible by a generalization of the Schwinger-Keldysh path-integral formalism in which the physical time can be re-parametrized to arbitrary contours in the complex plane. Strong relations between correlation functions, such as the fluctuation-dissipation theorems, are derived as immediate consequences of this symmetry of equilibrium. In this view, quantum non-equilibrium dynamics -- e.g. when driving with a time-dependent potential -- are seen as symmetry-breaking processes. The symmetry-breaking terms of the action are identified as a measure of irreversibility, or entropy creation, defined at the level of a single quantum trajectory. Moreover, they are shown to obey quantum fluctuation theorems. These results extend stochastic thermodynamics to the quantum realm.

• Araújo et al., Axiomatic construction of quantum Langevin equations
  J. Stat. Mech. 2019, 053101 (2019) [Crossref]
• Chakraborty et al., Nonequilibrium field theory for dynamics starting from arbitrary athermal initial conditions
  Phys. Rev. B 99, 054306 (2019) [Crossref]
• Altland et al., Symmetry Classes of Open Fermionic Quantum Matter
  Phys. Rev. X 11, 021037 (2021) [Crossref]
• Minami et al., Thermodynamic entropy as a Noether invariant in a Langevin equation
  J. Stat. Mech. 2020, 013213 (2020) [Crossref]
• Fei et al., Nonequilibrium Green’s Function’s Approach to the Calculation of Work Statistics
  Phys. Rev. Lett. 124, 240603 (2020) [Crossref]
• Paz et al., Time-reversal symmetry breaking and emergence in driven-dissipative Ising models
  SciPost Phys. 12, 066 (2022) [Crossref]
• Sinha et al., On the bound states and correlation functions of a class of Calogero-type quantum many-body problems with balanced loss and gain
  J. Phys. A: Math. Theor. 52, 505203 (2019) [Crossref]
• Cavina et al., A convenient Keldysh contour for thermodynamically consistent perturbative and semiclassical expansions
  SciPost Phys. 15, 209 (2023) [Crossref]
• Hongo et al., Effective Lagrangian for Nambu-Goldstone modes in nonequilibrium open systems
  Phys. Rev. D 103, 056020 (2021) [Crossref]
• Rodriguez-Nieva et al., Far-from-equilibrium universality in the two-dimensional Heisenberg model
  Proc. Natl. Acad. Sci. U.S.A. 119, e2122599119 (2022) [Crossref]
• Li et al., Far-from-equilibrium universality in two-dimensional Heisenberg antiferromagnets
  Phys. Rev. B 108, 144303 (2023) [Crossref]
• Gu et al., Tensor-network approach to work statistics for one-dimensional quantum lattice systems
  Phys. Rev. Research 4, 033193 (2022) [Crossref]
• Špička et al., Relation between full NEGF, non-Markovian and Markovian transport equations
  Eur. Phys. J. Spec. Top. 230, 771 (2021) [Crossref]
• Hongo et al., Effective field theory of time-translational symmetry breaking in nonequilibrium open system
  J. High Energ. Phys. 2019, 131 (2019) [Crossref]
• Potts, Certifying Nonclassical Behavior for Negative Keldysh Quasiprobabilities
  Phys. Rev. Lett. 122, 110401 (2019) [Crossref]
• Mathey et al., Absence of Criticality in the Phase Transitions of Open Floquet Systems
  Phys. Rev. Lett. 122, 110602 (2019) [Crossref]
• Mathey et al., Dynamic renormalization group theory for open Floquet systems
  Phys. Rev. B 102, 134307 (2020) [Crossref]
• Knotz et al., Entropy bound for time reversal markers
  Front. Phys. 11, 1331835 (2024) [Crossref]
• Yeo, Symmetry and its breaking in a path-integral approach to quantum Brownian motion
  Phys. Rev. E 100, 062107 (2019) [Crossref]
• Cugliandolo et al., Role of initial conditions in the dynamics of quantum glassy systems
  J. Stat. Mech. 2019, 023301 (2019) [Crossref]