# American Institute of Mathematical Sciences

January  1996, 2(1): 121-140. doi: 10.3934/dcds.1996.2.121

## Lorenz equations part II: "randomly" rotated homoclinic orbits and chaotic trajectories

 1 Department of Mathematics, University of Pittsburgh, Pittsburgh, PA 15260

Received  March 1995 Published  October 1995

The Lorenz equations are a system of ordinary differential equations

$x' =s(y-x), \quad y'= Rx -y-xz, \quad z'= xy -qz,$

where $s$, $R$, and $q$ are positive parameters. We show by a purely analytic proof that for each non-negative integer $N$, there are positive parameters $s, q,$ and $R$ such that the Lorenz system has homoclinic orbits associated with the origin (i.e., orbits that tend to the origin as $t\to \pm \infty$) which can rotate around the $z$-axis $N/2$ times; namely, the $x$-component changes sign exactly $N$ times, the $y$-component changes sign exactly $N+1$ times, and the zeros of $x$ and $y$ are simple and interlace.

Citation: Xinfu Chen. Lorenz equations part II: "randomly" rotated homoclinic orbits and chaotic trajectories. Discrete & Continuous Dynamical Systems - A, 1996, 2 (1) : 121-140. doi: 10.3934/dcds.1996.2.121
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