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arXiv · 1403.0022

Noise prevents infinite stretching of the passive field in a stochastic vector advection equation

Franco Flandoli·Mario Maurelli·Mikhail Neklyudov
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Abstract

A linear stochastic vector advection equation is considered; the equation may model a passive magnetic field in a random fluid. When the driving velocity field is rough but deterministic, in particular just Hölder continuous and bounded, one can construct examples of infinite stretching of the passive field, arising from smooth initial conditions. The purpose of the paper is to prove that infinite stretching is prevented if the driving velocity field contains in addition a white noise component.

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Franco Flandoli, Mario Maurelli, Mikhail Neklyudov. 2014-02-28. Noise prevents infinite stretching of the passive field in a stochastic vector advection equation. https://doi.org/10.1007/s00021-014-0187-0

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