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arXiv · 0907.1569

Generalization of the Second Law for a Nonequilibrium Initial State

H. -H. Hasegawa·J. Ishikawa·K. Takara·D. J. Driebe
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Abstract

We generalize the second law of thermodynamics in its maximum work formulation for a nonequilibrium initial distribution. It is found that in an isothermal process, the Boltzmann relative entropy (H-function) is not just a Lyapunov function but also tells us the maximum work that may be gained from a nonequilibrium initial state. The generalized second law also gives a fundamental relation between work and information. It is valid even for a small Hamiltonian system not in contact with a heat reservoir but with an effective temperature determined by the isentropic condition. Our relation can be tested in the Szilard engine, which will be realized in the laboratory.

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H. -H. Hasegawa, J. Ishikawa, K. Takara, D. J. Driebe. 2009-07-09. Generalization of the Second Law for a Nonequilibrium Initial State. https://doi.org/10.1016/j.physleta.2009.12.042

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