Julian Schwinger: Architect of Quantum Field Theory

OV Digital Desk

Julian Seymour Schwinger (12 February 1918 – 16 July 1994) was an American theoretical physicist. He won the Nobel Prize in Physics in 1965.

Life and Career

He was born on 12 February 1918, in New York City, U.S. He got a bachelor’s degree in 1937. He published his first paper in physics at 16 and by 17 he was doing advanced calculations. He had started writing a paper titled ‘Magnetic Scattering of Neutrons’, which was submitted to Physical Review. He got his doctorate in 1939 from Columbia University.

Julian Schwinger joined the University of California, Berkeley as a National Research Council Fellow after getting his Ph.D. in 1939. In 1940, he started working for J Robert Oppenheimer as a research associate. He got his regular academic job at Purdue University, Indiana, in the summer of 1941. He was promoted to assistant professor the following year. In 1942, Schwinger started working on microwave propagation in microwave cavities. In 1943, he joined the Radiation Laboratory at MIT.

With his nuclear physics knowledge, he developed the theory of nuclear scattering, which helped design radars. He also solved microwave problems while working at the Radiation Laboratory. He used these results to come up with many of his famous theories. Also, he gave a bunch of lectures about waveguides. During this time, his lectures showed his incredible analytical skills as well as his depth of knowledge. A book based on these lectures was published in 1968 called ‘Discontinuities in Waveguides’.

He accepted an appointment at Harvard University in 1945 and in 1947, he was promoted to the post of full professor, becoming one of the school’s youngest full professors. He also developed the concept of renormalization in September that explained the Lamb Shift in electron magnetic fields. In 1948-1949, he published a series of papers titled ‘Quantum Electrodynamics’ (Parts I, II, and III) in Physics Review, which was incredibly popular.

He left Harvard and joined the University of California at Los Angeles in 1972. There he continued to work on source theory, which is the mathematical symbolism of high-energy physics manipulations. Julian Seymour Schwinger died on 16 July 1994, in Los Angeles, California, U.S.

Major Works

His best-known work is quantum electrodynamics (QED). Not only did he develop the original QED formalism in several fundamental papers, but he made it more practical for calculations. Quantum field theory has gained a new dimension as a result of his discoveries.

Over the course of his career, Schwinger published around 200 papers and wrote a few books. He also acted as an academic advisor to around 73 doctoral students and 20 post-doctoral students. Most of them went on to become famous physicists, including three Nobel laureates. His theories still influence modern physics.

Award and Legacy

In 1965, Julian Schwinger shared the Nobel Prize in Physics with Richard Feynman and Shinichiro Tomonaga. They all worked independently, but their fundamental work in quantum electrodynamics had a huge impact on QED. Schwinger also won the Nature of Light Award of the US National Academy of Sciences in 1949, the Albert Einstein Award in 1951, and the US National Medal of Science in 1964.

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