Local equilibria and linearized stability
In a C¹ planar autonomous system, equilibria are zeros of the vector field.
Key knowledge
In a C¹ planar autonomous system, equilibria are zeros of the vector field. If the Jacobian eigenvalues have nonzero real parts, negative real parts give a local attracting equilibrium, positive real parts give a source, and opposite-sign real eigenvalues give a saddle.
Conditions and scope
- This is local classification near a hyperbolic equilibrium.
- Purely imaginary or zero-real-part eigenvalues do not settle nonlinear stability.
Sources · 1
References
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Evidence and review
Section 8.2.2 Table 8.1, stability definitions and section 8.2.3 center counterexample.
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