Pre-requisites for path integral formulation??? Does anybody have any idea of the pre-requisites to learn Feynmann's path integral formulation? (properly) Right about now, I'm still learning about Lagrangian and Hamiltonian mechanics which focuses on the principle of least action. Right now, the only knowledge that I have about quantum mechanics are the basic qualitative principles and the simple quantitative description of them. (which uses calculations that do not exceed multivariable calculus) As for my math proficiency, I'm just starting on real analysis, functions of a complex variable and I am halfway through ordinary differential equations. Are there any more pre-requisites that do not include what I do not already know or what I'm currently studying? I'd appreciate your feedback. Thanks.