Applications of Sard's Theorem. I am writing my Bachelors Thesis about Sard's Theorem and I was asking myself if there are any good applications of it or the direct consequences (Whitneys Embedding and Morse functions) in physics or geometric analysis for example. I found only one example from electrostatics online, some hints would be appriciated!
 A: There are more applications in differential topology than the ones you mention. Two main ones are the approximation theorems (of Whitney too), which you can see for example in [Introduction to Smooth Manifolds, John.M.Lee] or the Brouwer fixed point theorem, which you can see very short and nicely in [Topology from the Differential Viewpoint, John.W.Milnor].         
There is also a nice topology differentiable theory called "degree theory" which studies the zeroes of continuous functions. The building of this theory widely uses the Sard theorem in order to prove several properties of an application called "degree". If you are interested, you can have a look at  [Mapping Degree Theory, Enrique Outerelo, Jesús M. Ruiz]. With a quick search of the word "Sard" you can find plenty of applications. This theory also admits a generalization to Banach spaces, which might be something you are looking for, since this has many applications to EDP's. However, I do not know yet any good reference for this... 
Sorry, I do not know about any more specific applications in physics, but I hope this helps!
