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arXiv · 0712.0240

Non-Markovian diffusion equations and processes: analysis and simulations

Abstract

In this paper we introduce and analyze a class of diffusion type equations related to certain non-Markovian stochastic processes. We start from the forward drift equation which is made non-local in time by the introduction of a suitable chosen memory kernel K(t). The resulting non-Markovian equation can be interpreted in a natural way as the evolution equation of the marginal density function of a random time process l(t). We then consider the subordinated process Y(t)=X(l(t)) where X(t) is a Markovian diffusion. The corresponding time evolution of the marginal density function of Y(t) is governed by a non-Markovian Fokker-Planck equation which involves the memory kernel K(t). We develop several applications and derive the exact solutions. We consider different stochastic models for the given equations providing path simulations.

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BibTeXRIS

Antonio Mura, Murad S. Taqqu, Francesco Mainardi. 2008-05-23. Non-Markovian diffusion equations and processes: analysis and simulations. https://doi.org/10.1016/j.physa.2008.04.035

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