AppDynSys : Bifurcation Examples : Hysteresis

Along a certain slice of the 2-parameter unfolding of a supercritical pitchfork bifurcation, you can observe hysteresis. Let's say you evolve to a stable equilibrium. Now slowly change the parameter -- the equilibrium slowly changes, unless you hit a saddle-node bifurcation. Then, you might fly off to a new stable equilibrium. The hysteresis is seen when you try to undo that change.