For 10 points, name this longtime Caltech physicist and author of the book QED, perhaps best known for his namesake diagrams.
He's not Onsager, but he showed that the superfluid velocity of vortices in single-component superfluid systems is quantized and that said quantization depends only on Planck's constant and mass. In studying Dirac fields, he developed a way of simplifying expressions involving gamma matrices are simplified by using his namesake slash notation, and this man and Landau used a namesake ansatz to attack the problem of helium-II superfluidity. This physicist developed the (*) path integral formulation of quantum mechanics, though he may be better known for developing a way to conveniently show how real particles interact to produce virtual photons in order to simplify perturbative calculations. For 10 points, name this longtime Caltech physicist and author of the book QED, perhaps best known for his namesake diagrams.
He's not Onsager, but he showed that the superfluid velocity of vortices in single-component superfluid systems is quantized and that said quantization depends only on Planck's constant and mass.
Richard Phillips Feynman