This is the maths which I regard as essential to an understanding of modern physics. I have kept it to a minimum and made the treatments as simple as possible. Without it, I don’t think it is possible to have a full understanding of either quantum theory or general relativity, but if the mathematics is understood then neither of those theories hold any great problems. You don’t need it all at once. You can skip past it, and come back to it when needed.
Miscellaneous Methods