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arXiv · 1202.2904

An analytic approximation to the Diffusion Coefficient for the periodic Lorentz Gas

C. Angstmann·G. P. Morriss
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Abstract

An approximate stochastic model for the topological dynamics of the periodic triangular Lorentz gas is constructed. The model, together with an extremum principle, is used to find a closed form approximation to the diffusion coefficient as a function of the lattice spacing. This approximation is superior to the popular Machta and Zwanzig result and agrees well with a range of numerical estimates.

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C. Angstmann, G. P. Morriss. 2012-02-14. An analytic approximation to the Diffusion Coefficient for the periodic Lorentz Gas. https://doi.org/10.1016/j.physleta.2012.04.045

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