Instanton Theory of Burgers Shocks and Intermittency

L. Moriconi

doi:10.1103/physreve.79.046324

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arXiv · 0812.1611

Instanton Theory of Burgers Shocks and Intermittency

L. Moriconi

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Abstract

A lagrangian approach to Burgers turbulence is carried out along the lines of the field theoretical Martin-Siggia-Rose formalism of stochastic hydrodynamics. We derive, from an analysis based on the hypothesis of unbroken galilean invariance, the asymptotic form of the probability distribution function of negative velocity-differences. The origin of Burgers intermittency is found to rely on the dynamical coupling between shocks, identified to instantons, and non-coherent background fluctuations, which, then, cannot be discarded in a consistent statistical description of the flow.

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L. Moriconi. 2008-12-09. Instanton Theory of Burgers Shocks and Intermittency. https://doi.org/10.1103/physreve.79.046324

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