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arXiv · 1509.09247

A method for Hamiltonian truncation: A four-wave example

Thiago F. Viscondi·Iberê L. Caldas·Philip J. Morrison
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Abstract

A method for extracting finite-dimensional Hamiltonian systems from a class of 2+1 Hamiltonian mean field theories is presented. These theories possess noncanonical Poisson brackets, which normally resist Hamiltonian truncation, but a process of beatification by coordinate transformation near a reference state is described in order to perturbatively overcome this difficulty. Two examples of four-wave truncation of Euler's equation for scalar vortex dynamics are given and compared: one a direct non-Hamiltonian truncation of the equations of motion, the other obtained by beatifying the Poisson bracket and then truncating.

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Thiago F. Viscondi, Iberê L. Caldas, Philip J. Morrison. 2015-09-30. A method for Hamiltonian truncation: A four-wave example. https://arxiv.org/abs/1509.09247

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