Topological classification of periodic orbits in Lorenz system<xref rid="cpb_27_8_080501_fn1" ref-type="fn">*</xref> <fn id="cpb_27_8_080501_fn1"><label>*</label> <p>Project supported by the National Natural Science Foundation of China (Grant Nos. 11647085, 11647086, and 11747106), the Applied Basic Research Foundation of Shanxi Province, China (Grant No. 201701D121011), and the Natural Science Research Fund of North University of China (Grant No. XJJ2016036).</p></fn>

Topological classification of periodic orbits in Lorenz system* *

Project supported by the National Natural Science Foundation of China (Grant Nos. 11647085, 11647086, and 11747106), the Applied Basic Research Foundation of Shanxi Province, China (Grant No. 201701D121011), and the Natural Science Research Fund of North University of China (Grant No. XJJ2016036).

Dong Chengwei^†

(color online) (a) 2D projection of a trajectory in the Lorenz flow at time t = 100. (b) Return map for the Poincaré section z = 27 after reduction to x > 0 by virtue of inversion symmetry.