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Short-time fluctuations of displacements and work

Ramses van Zon·S. S. Ashwin·E. G. D. Cohen
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Abstract

A recent theorem giving the initial behavior of very short-time fluctuations of particle displacements in classical many-body systems is discussed. It has applications to equilibrium and non-equilibrium systems, one of which is a series expansion of the distribution of work fluctuations around a Gaussian function. To determine the time-scale at which this series expansion is valid, we present preliminary numerical results for a Lennard-Jones fluid. These results suggest that the series expansion converges up to time scales on the order of a picosecond, below which a simple Gaussian function for the distribution of the displacements can be used.

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Ramses van Zon, S. S. Ashwin, E. G. D. Cohen. 2006-11-22. Short-time fluctuations of displacements and work. https://doi.org/10.1016/j.crhy.2007.05.011

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