Feynman developed a revolutionary approach to calculating interactions between charged particles and photons using visual representations called Feynman diagrams. These diagrams simplified complex calculations and provided a deeper intuitive understanding of QED.

Feynman formulated a new approach to quantum mechanics known as the path integral formulation, which provided an alternative to the traditional Schrödinger equation. This formulation emphasized the concept of summing over all possible paths a particle could take.

Feynman shared the 1965 Nobel Prize in Physics with Julian Schwinger and Shin'ichirō Tomonaga for their fundamental work in quantum electrodynamics. This prize recognized their independent but complementary contributions to developing a consistent and accurate theory of QED.