Translation of Stueckelberg paper

Inspired by Tim Hosgood’s project on translating papers in mathematics written in French to English, I decided to take a stab at translating a paper from French as well. Since I wanted a short paper to start off, I chose a paper by E. Stueckelberg on proper-time in quantum mechanics. The paper is only a page long and it was fairly quick to translate. I stuck to the original notation but made changes to the sentence structure to make things clearer.

Translating it was good fun and it was a good change from writing my thesis. I think I might continue with other papers from physics as well. The translation can be found here.