Lorenz integrable system moves \`a la Poinsot
Abstract
A transformation is derived which takes Lorenz integrable system into the well-known Euler equations of a free-torque rigid body with a fixed point, i.e. the famous motion \`a la Poinsot. The proof is based on Lie group analysis applied to two third order ordinary differential equations admitting the same two-dimensional Lie symmetry algebra. Lie's classification of two-dimensional symmetry algebra in the plane is used. If the same transformation is applied to Lorenz system with any value of parameters, then one obtains Euler equations of a rigid body with a fixed point subjected to a torsion depending on time and angular velocity. The numerical solution of this system yields a three-dimensional picture which looks like a "tornado" whose cross-section has a butterfly-shape. Thus, Lorenz's {\em butterfly} has been transformed into a {\em tornado}.
Cite
@article{arxiv.nlin/0209043,
title = {Lorenz integrable system moves \`a la Poinsot},
author = {M. C. Nucci},
journal= {arXiv preprint arXiv:nlin/0209043},
year = {2009}
}
Comments
14 pages, 6 figures