Consider the system \[ \begin {aligned} \dot {x} &= \mu +x^2+y^2,\\ \dot {y} &= -y+x^2 \end {aligned} \]
- State the Center Manifold Theorem for rest points. Briefly explain its importance in bifurcation theory.
- Using an approximate center manifold, determine the nature of the bifurcation at the origin at \(\mu =0\).