The following is a list of physics concepts and mathematical methods and 
techniques. You should understand what is meant by each item on the list.

- equilibria, static and dynamic
- normal modes, in homogenous and inhomogenous media
- normal mode stability
- local dispersion relation, eigenvalues and eigenfunctions
- linear vs nonlinear PDE's
- reduced equations
- annihilators
- ideal fluid eqns vs dissipative NS fluid eqns
- NS eqns as first order correction to ideal fluids
- linearization of PDE's
- frequency space and disparate frequencies
- numerical stability of PDE's
- self-consistent check
- method of regions
- asymptotic matching