Strange Nonchaotic Attractor

Gopy-Prasad map Feudel-Pikovsky-Kurths Nishikawa-Kaneko α (amplitude) 3.00 β (coupling) 0.30 ω (freq ratio) 0.618 Pause Reset Clear Trail

Lyapunov: computing…

A strange nonchaotic attractor (SNA) has fractal geometry yet non-positive largest Lyapunov exponent (λ≤0). SNAs exist in quasiperiodically driven systems — neither periodic nor chaotic. Gopy-Prasad: x_{n+1} = tanh(α·x_n + β·cos(2πθ_n)), θ_{n+1} = θ_n + ω (mod 1), ω = golden ratio.