Source on Julian Schwinger

“It's true that he had a funny style. His lecture was precise. He had the voice of a radio announcer. Everything was in perfect sentences, grammatically perfect. The formulas were all clearly written on the board. The talk was so designed that he would be at the blackboard nearest the exit door at the end of the lecture. He would end the lecture and... immediately slip out the door and disappear so that his graduate students could not track him down too easily.”

“He argued to me that electrons and muons, which are particles, charged leptons we call them, were known... He said that if we're going to have a quantum number that distinguishes electrons from muons, then surely... it should not be e- and μ- that have... lepton number, it should be the e- and the μ+. So... that way... charge and the new quantum number can distinguish electrons from muons... and it followed that there had to be two kinds of neutrinos in nature. So built into the way he taught... particle physics was the fact that there are two kinds of neutrinos. ...It was acknowledged as a technical possibility by some people, but it... wouldn't be known until 1963. This was in the 1950s.”

“Schwinger had... been working on radar and solved some radar related... electrodynamic problems, classical electrodynamic theory problems that nobody else could approach... [A]s a calculator he was amazing... phenomenal. ...You can well argue that radar... as well as new developments in bomb technology, in fuses, played a more important role than nuclear weapons [in World War II].”