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arXiv · 1306.3858

Path-wise versus kinetic modeling for equilibrating non-Langevin jump-type processes

Abstract

We discuss two independent methods of solution of a master equation whose biased jump transition rates account for long jumps of L\'{e}vy-stable type and nonetheless admit a Boltzmannian (thermal) equilibrium to arise in the large time asymptotics of a probability density function $\rho (x,t)$. Our main goal is to demonstrate a compatibility of a {\it direct} solution method (an explicit, albeit numerically assisted, integration of the master equation) with an {\it indirect} path-wise procedure, recently proposed in [Physica {\bf A 392}, 3485, (2013)] as a valid tool for a dynamical analysis of non-Langevin jump-type processes. The path-wise method heavily relies on an accumulation of large sample path data, that are generated by means of a properly tailored Gillespie's algorithm. Their statistical analysis in turn allows to infer the dynamics of $\rho (x,t)$. However, no consistency check has been completed so far to demonstrate that both methods are fully compatible and indeed provide a solution of the same dynamical problem. Presently we remove this gap, with a focus on potential deficiencies (various cutoffs, including those upon the jump size) of approximations involved in solution protocols.

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BibTeXRIS

Mariusz Żaba, Piotr Garbaczewski, Vladimir Stephanovich. 2013-06-17. Path-wise versus kinetic modeling for equilibrating non-Langevin jump-type processes. https://doi.org/10.2478/s11534-014-0432-4

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