Partial Differential Equations in Physics

The topic with which I regularly conclude my six-term series of lectures in Munich is the partial differential equations of physics. We do not really deal with mathematical physics, but with physical mathematics; not with the mathematical formulation of physical facts, but with the physical motivation of mathematical methods. The oftmentioned "prestabilized harmony between what is mathematically interesting and what is physically important is met at each step and lends an esthetic - I should lik