Intermittent incommensurate chaos

Abstract

Near the onset of intermittent chaos from quasiperiodic motion lying on an attracting 2D torus with rotation number ρ= ω 2/ ω 1=(√5−1)/2, the power spectrum of the cartesian coordinate of the intersection point on the Poincaré section is studied. The Poincaré section is distorted from the ellipse near the onset of chaos. Then a sequence of spectral lines are excited at frequencies Ω i = ρ iΩ 2, (i=1,2,…) . Their intensities are found to obey the power law Ω 4 i or Ω 2 i for i ⪢ 1 according as the Poincaré section has a sharp wrinkle or not. A similar spectrum is obtained also in the chaotic regime ε > 0. The mean value of time intervals of quasiperiodic states between two consecutive bursts and the square root of their variance are found to be inversely proportional to ε near the onset point g3 = 0.