English

Thermofield Dynamics of Time-Dependent Boson and Fermion Systems

Quantum Physics 2007-05-23 v1

Abstract

We formulate the thermofield dynamics for time-dependent systems by combining the Liouville-von Neumann equation, its invariant operators, and the basic notions of thermofield dynamics. The new formulation is applied to time-dependent bosons and fermions by using the time-dependent annihilation and creation operators that satisfy the Liouville-von Neumann equation. It is shown that the thermal state is the time- and temperature-dependent vacuum state and a general formula is derived to calculate the thermal expectation value of operators.

Keywords

Cite

@article{arxiv.quant-ph/0308053,
  title  = {Thermofield Dynamics of Time-Dependent Boson and Fermion Systems},
  author = {Sang Pyo Kim and F. C. Khanna},
  journal= {arXiv preprint arXiv:quant-ph/0308053},
  year   = {2007}
}

Comments

RevTex4 11 pages, no figure

R2 v1 2026-07-22T19:40:35.400Z