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arXiv · 1802.02173

Coercivity, hypocoercivity, exponential time decay and simulations for discrete Fokker-Planck equations

Guillaume Dujardin·Frédéric Hérau·Pauline Lafitte
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Abstract

In this article, we propose and study several discrete versions of homogeneous and inhomogeneous one-dimensional Fokker-Planck equations. In particular, for these discretizations of velocity and space, we prove the exponential convergence to the equilibrium of the solutions, for time-continuous equations as well as for time-discrete equations. Our method uses new types of discrete Poincar\'e inequalities for a "two-direction" discretization of the derivative in velocity. For the inhomogeneous problem, we adapt hypocoercive methods to the discrete cases.

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Guillaume Dujardin, Frédéric Hérau, Pauline Lafitte. 2018-02-06. Coercivity, hypocoercivity, exponential time decay and simulations for discrete Fokker-Planck equations. https://arxiv.org/abs/1802.02173

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