By the end of the course, the student will learn the following components of the theory:
- Domains for the differential equations, integral curves, trajectories, and phase portraits.
- The definitions of local and global existence and uniqueness of solutions. Examples of the phenomena in models.
- Theorems of existence and uniqueness of solutions with various sufficient conditions. The instance of nowhere uniqueness.
- Definitions of continuous and differentiable dependence of solutions on initial data and parameters.
- Theorems on the dependence of solutions on initial data and parameters.
- Method of the small parameter in the non-critical case.
- Analysis of linear homogeneous and inhomogeneous systems of differential equations, focusing on the methods of solutions, description of individual and collective behaviour. Spaces of solutions.
- Periodic systems of linear equations, criteria of existence for periodic solutions.
- Higher-order linear equations. Connection with the first-order linear systems. The initial value problem.
- Definitions of Lyapunov stability. Linear, quasilinear systems. Stability by linearization.
- Lyapunov’s second method. Application to mechanical and electrical models.