Feynman and Path Integrals
•I read Quantum Man by Lawrence Krauss for the story of the physics that Feynman developed and worked on.
•After the war, Feynman was recruited by many universities and decided to go to Cornell to work with Hans Bethe.
•There he developed his new Path Integral formulation of Quantum Mechanics.
•Feynman didn’t really use this to rigorously develop his diagrams or rules, so we put that in an appendix.
•We do teach the Path Integral formulation in graduate courses to show students how Feynman rules can be derived, however.