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arXiv · 1110.2217

Temperature of a Decoherent Oscillator with Strong Coupling

William G. Unruh
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Abstract

The temperature of an oscillator coupled to the vacuum state of a heat bath via ohmic coupling is non-zero, as measured by the reduced density matrix of the oscillator. This paper shows that the actual temperature, as measured by a thermometer is still zero (or in the thermal state of the bath, the temperature of the bath). The decoherence temperature is due to "false-decoherence", with the heat bath state being dragged along with the oscillator.

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William G. Unruh. 2011-10-10. Temperature of a Decoherent Oscillator with Strong Coupling. https://doi.org/10.1098/rsta.2011.0495

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