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Chinese Physics Letters

Derivation of Tilde Rules in η - ξ Spacetime

Jianping Zuo, Yuanxing Gui

Published Jan 1, 1998• 1 citation
Publisher

Abstract

The M operation is introduced in η - ξ spacetime to derive the tilde rules in thermo field dynamics (TFD). This leads to an explanation of the tilde system in TFD as the system in region II of η - ξ spacetime.
DOI
10.1088/0256-307x/15/1/001

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The tilde substitution law (which will be called in this paper the thermal state condition) plays an important role in determining the temperature-dependent ground state in thermo field dynamics (a real-time operator formalism of quantum field theory at finite temperature). Rules which define the phase conventions for the tilde substitution for any arbitrary Heisenberg operator are derived. These rules also lead to a clear correspondence between the perturbation series obtained in thermo field dynamics and the path-ordered formalism of the statistical average.