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Measuring Nonequilibrium Temperature of Forced Oscillators

Takahiro Hatano·David Jou
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Abstract

The meaning of temperature in nonequilibrium thermodynamics is considered by using a forced harmonic oscillator in a heat bath, where we have two effective temperatures for the position and the momentum, respectively. We invent a concrete model of a thermometer to testify the validity of these different temperatures from the operational point of view. It is found that the measured temperature depends on a specific form of interaction between the system and a thermometer, which means the zeroth law of thermodynamics cannot be immediately extended to nonequilibrium cases.

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Takahiro Hatano, David Jou. 2002-07-17. Measuring Nonequilibrium Temperature of Forced Oscillators. https://doi.org/10.1103/physreve.67.026121

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