The normal form: dr/dt = μr - r³, dθ/dt = ω
When μ < 0: stable fixed point.
When μ = 0: bifurcation.
When μ > 0: limit cycle with radius √μ.
When μ < 0: stable fixed point.
When μ = 0: bifurcation.
When μ > 0: limit cycle with radius √μ.
Display
Phase portrait (x,y)
x(t) time series
Bifurcation diagram
r(t) — amplitude