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Quantum phase space distributions in thermofield dynamics

S. Chaturvedi·V. Srinivasan·G. S. Agarwal
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Abstract

It is shown that the the quantum phase space distributions corresponding to a density operator $ρ$ can be expressed, in thermofield dynamics, as overlaps between the state $\mid ρ>$ and "thermal" coherent states. The usefulness of this approach is brought out in the context of a master equation describing a nonlinear oscillator for which exact expressions for the quantum phase distributions for an arbitrary initial condition are derived.

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S. Chaturvedi, V. Srinivasan, G. S. Agarwal. 1998-10-08. Quantum phase space distributions in thermofield dynamics. https://doi.org/10.1088/0305-4470%2F32%2F10%2F009

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