TY - JOUR

T1 - Self-consistent analysis of a thermally dissipative quantum field system

T2 - Korenman's model

AU - Hardman, I.

AU - Umezawa, H.

AU - Yamanaka, Y.

N1 - Funding Information:
The authors would like to thank T. Arimitsu, J. Hebron, K. Nakamura, Y. Nakawaki, N.J. Papastamatiou and 0. Wong for their valuable discussions. This work was partially supported by the Natural Sciences and Engineering Research Council, Canada, and the Dean of Science, Faculty of Science, the University of Alberta. One of the authors (I.H.) would like to thank the Government of Canada and the Association of Universities and Colleges of Canada for financial support through a Canadian Commonwealth Scholarship.

PY - 1989/4/15

Y1 - 1989/4/15

N2 - Using the Schwinger-Keldysh path-ordering method, a favoured method for doing non-equilibrium quantum field theory, Korenman analyzed a simple model from quantum optics. We study the same model using the recently developed non-equilibrium thermo field dynamics (TFD), and make a comparison of these two methods. TFD can deal with time-dependent non-equilibrium situations caused by the initial conditions being out of equilibrium, while Korenman considered a stationary state maintained by an assumed external pumping mechanism. The explicit TFD calculation at one loop level shows the approach of the system to equilibrium which is described by the master equation derived from the self-consistent renormalization condition. Although both of the methods give practically the same dissipative coefficient in this order of approximation, we would find a larger difference between them in a higher order calculation because of the difference of unperturbative propagators. We also briefly consider the inclusion of a simple pumping mechanism for the system in TFD.

AB - Using the Schwinger-Keldysh path-ordering method, a favoured method for doing non-equilibrium quantum field theory, Korenman analyzed a simple model from quantum optics. We study the same model using the recently developed non-equilibrium thermo field dynamics (TFD), and make a comparison of these two methods. TFD can deal with time-dependent non-equilibrium situations caused by the initial conditions being out of equilibrium, while Korenman considered a stationary state maintained by an assumed external pumping mechanism. The explicit TFD calculation at one loop level shows the approach of the system to equilibrium which is described by the master equation derived from the self-consistent renormalization condition. Although both of the methods give practically the same dissipative coefficient in this order of approximation, we would find a larger difference between them in a higher order calculation because of the difference of unperturbative propagators. We also briefly consider the inclusion of a simple pumping mechanism for the system in TFD.

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U2 - 10.1016/0378-4371(89)90024-1

DO - 10.1016/0378-4371(89)90024-1

M3 - Article

AN - SCOPUS:4243585788

VL - 156

SP - 853

EP - 875

JO - Physica A: Statistical Mechanics and its Applications

JF - Physica A: Statistical Mechanics and its Applications

SN - 0378-4371

IS - 3

ER -