Provoked by the previous blog post about the path integrals, Frank S. sent me two fascinating 1924 papers by Gregor Wentzel which "almost" defined the Feynman's path integral definition of quantum mechanics but two decades earlier (and a year before Heisenberg started quantum mechanics as we know it). If you find English somewhat more comprehensible than German, like I do, you may read a 1998 review of these papers by Salvatore Antoci and Dierck-E. Liebscher
Wentzel's Path Integrals (PDF may be downloaded there)which probably contains more than what we will actually ever need, unless we plan to write a detailed book about the history of science. First, Wentzel may sound like a forgotten name. But on this blog, you find it in two previous texts. He had something to do with dispersion and Kramers etc. After all, Wentzel's name starts with a W, like WKB does, and indeed, he is also the first guy remembered in the WKB acronym. But how many people know what (J)WKB stands for now?
Just a Czech comment. Wentzel sounds very German because it's spelled in a German way. But it's just a Germanization of the Czech, Slavic name Václav. Why? Because the original form of the name, used some 1000 years ago, was Věnceslav (like Víceslav) which really means "more fame" or "more famous".
Ironically enough, "Boleslav" had the same meaning ("bole" is still a Russian word for "more"). Boleslav was the brother who murdered saint Václav. They were brothers but their first names had the same meaning. English adopted the old Czech "Věnceslav" as its (Good King) Wenceslaus, German shortened it to Wenzl or Wentzel, and modern Czech shortened it to Václav (or, colloquially, Vašek or Venca, the latter is probably a Bohemization of the German name Wentzel; note that Venclovský was the first Czech who swam over the English Channel while David Vencl – the surname is just a Bohemian respelled Wentzel – recently improved the world record in swimming under the ice to 81 meters, a great Czech dude)...