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arXiv · 1604.00867

Statistics of the stochastically-forced Lorenz attractor by the Fokker-Planck equation and cumulant expansions

Altan Allawala·J. B. Marston
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Abstract

We investigate the Fokker-Planck description of the equal-time statistics of the three-dimensional Lorenz-63 attractor with additive white noise. The invariant measure is found by computing the zero (or null) mode of the linear Fokker-Planck operator as a problem of sparse linear algebra. Two variants are studied: A self-adjoint construction of the linear operator, and the replacement of diffusion with hyperdiffusion. We also access the low-order statistics of the system by a perturbative expansion in equal-time cumulants. Comparison is made to statistics obtained by the standard approach of accumulation via direct numerical simulation. Theoretical and computational aspects of the Fokker-Planck and cumulant expansion methods are discussed.

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Altan Allawala, J. B. Marston. 2016-04-04. Statistics of the stochastically-forced Lorenz attractor by the Fokker-Planck equation and cumulant expansions. https://doi.org/10.1103/physreve.94.052218

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