Part 5/9:
Richard Feynman’s contributions to QFT were transformative, particularly through his introduction of Feynman diagrams. These visual tools help to describe and visualize particle interactions. Each line in a diagram represents a particle, while points at which these lines converge denote interactions.
Feynman's innovative approach not only simplified the complex calculations associated with QFT but also afforded physicists a clearer way to depict particle interactions. By treating certain fluctuations in quantum fields as "virtual particles," Feynman enabled scientists to approximate the results of these interactions without performing exhaustive calculations.