There he was involved in theoretical, experimental, and numerical work in theoretical physics, high-energy physics, nonlinear dynamics, fluid dynamics, nanotechnology, and robotics.
en.wikipedia.org Although related to theoretical physics, mathematical physics in this sense emphasizes the mathematical rigour of the same type as found in mathematics.
en.wikipedia.org In theoretical physics, however, this scruple can be set aside, by a process called nondimensionalization.
en.wikipedia.org That award praised his lucid, insightful, and influential reviews on partially conserved currents, gauge theories, instantons, and magnetic monopoles--subjects fundamental to theoretical physics.
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