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arXiv · 1905.07611

Large fluctuations in non-ideal coarse-grained systems

M. Reza Parsa·Alexander J. Wagner
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Abstract

Using the recently introduced Molecular Dynamics Lattice Gas (MDLG) approach, we test fluctuations of coarse-grained quantities. We show that as soon as the system can no longer be considered an ideal gas fluctuations fail to diminish upon coarse-graining as is usually expected. These results suggest that current approaches to simulating fluctuating hydrodynamics may have to be augmented to achieve quantitative results for systems with a non-ideal equation of state. The MDLG method gives a guidance to the exact nature of the fluctuation in such systems.

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M. Reza Parsa, Alexander J. Wagner. 2019-05-18. Large fluctuations in non-ideal coarse-grained systems. https://doi.org/10.1103/physrevlett.124.234501

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