Arnold Nordsieck

Arnold Theodore Nordsieck (1911–1971) was an American theoretical physicist known for his work with Felix Bloch on the infrared problem in quantum electrodynamics. Born in Marysville, Ohio, he earned a M.S. in physics at Ohio State University and a Ph.D. at the University of California, Berkeley, under Robert Oppenheimer. In 1935, as a postdoctoral researcher at Leipzig University with Werner Heisenberg, he collaborated with Bloch to solve the infrared problem, addressing discrepancies in scattering amplitudes by improving perturbation theory methods. Upon returning to the U.S., Nordsieck taught physics at Columbia University and later joined Bell Telephone Laboratories. From 1947 to 1961, he was a professor at the University of Illinois at Urbana-Champaign, where his students included Erwin Hahn. In 1950, he built a differential analyzer using surplus World War II electronic parts, leading to early computers at Lawrence Livermore National Laboratory and Purdue University. He developed the inertial electrostatic gyroscope (ESG) in 1953, used in nuclear submarines' inertial navigation systems for underwater location tracking. Nordsieck also proposed the Cornfield system, a computer-based decision-making system for ship defense using radar, one of the first applications of computer technology. With B. L Hicks, he applied Monte Carlo methods to solve nonlinear Boltzmann equations in gas dynamics. He was a 1955 Guggenheim Fellow and later worked at the General Research Corporation. The University of Illinois awards the Nordsieck Award for teaching excellence since 2002, recognizing outstanding physics educators. The University of California, Santa Barbara, also annually honors graduating physics seniors with research promise ...