Article,
Nonlinear problems in physics
Print edition, 20 (5): 27-33 (1967)
DOI: http://dx.doi.org/10.1063/1.3034303
Abstract
NONLINEAR PROBLEMS in physics are difficult to discuss for several reasons. First, what are nonlinear problems? Practically every problem in theoretical physics is governed by nonlinear mathematical equations, except perhaps quantum theory, and even in quantum theory it is a rather controversial question whether it will finally be a linear or nonlinear theory. Therefore by far the largest part of theoretical physics is devoted to nonlinear problems. Interactions of matter and fields are generally nonlinear, so that nonlinear problems play a central role in physics. In fact because nonlinearity is so basic to nature, it is possible that even a theory as fundamentally linear as quantum theory may ultimately have to be replaced by a nonlinear one.
