Saddle-node bifurcation

Summary

A saddle-node bifurcation is a change in a family of dynamical systems at which two equilibrium points meet and disappear. On one side of the critical parameter there are two equilibria, one stable and one unstable, and on the other side there are none nearby. It is the most common way in which equilibria are created or destroyed as a parameter varies. It is also called a fold bifurcation or a tangent bifurcation. See the definition.