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PubMed · 16210186

Coarse graining from coarse-grained descriptions.

Pep Español·Federico Vázquez
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Abstract

We present a generalization of Zwanzig's method of projection operators to the case where the underlying dynamics is not deterministic. The method allows us to perform a coarse graining of an already coarse-grained level of description in which fluctuations are important. The initial level of description is described by a Fokker-Planck equation and, under suitable approximations, the final slower level of description is also described by a Fokker-Planck equation. We illustrate the method for the simple case of the diffusion of colloidal particles at two levels of descriptions.

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ColloidsComputer SimulationKineticsModels, BiologicalModels, ChemicalModels, StatisticalParticle SizeQuantum TheoryRheologyJournal ArticleResearch Support, Non-U.S. Gov't

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Pep Español, Federico Vázquez. 2002-03-15. Coarse graining from coarse-grained descriptions.. https://doi.org/10.1098/rsta.2001.0935

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