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arXiv · 1203.0602

On perturbations of generalized Landau-Lifshitz dynamics

Mark Freidlin·Wenqing Hu
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Abstract

We consider deterministic and stochastic perturbations of dynamical systems with conservation laws in $\R^3$. The Landau-Lifshitz equation for the magnetization dynamics in ferromagnetics is a special case of our system. The averaging principle is a natural tool in such problems. But bifurcations in the set of invariant measures lead to essential modification in classical averaging. The limiting slow motion in this case, in general, is a stochastic process even if pure deterministic perturbations of a deterministic system are considered. The stochasticity is a result of instabilities in the non-perturbed system as well as of existence of ergodic sets of a positive measure. We effectively describe the limiting slow motion.

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Mark Freidlin, Wenqing Hu. 2012-03-03. On perturbations of generalized Landau-Lifshitz dynamics. https://doi.org/10.1007/s10955-011-0289-5

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