English

Lorenz integrable system moves \`a la Poinsot

Exactly Solvable and Integrable Systems 2009-11-07 v2 Mathematical Physics Dynamical Systems math.MP Chaotic Dynamics

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}.

Keywords

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

R2 v1 2026-07-22T18:10:00.577Z