Peter Gratton, Ph.D., is a New Orleans-based editor and professor with over 20 years of experience in investing, risk management, and public policy. Peter began covering markets at Multex (Reuters) ...

Nonlinear phenomena are phenomena, which, in contrast to a linear system, cannot be explained by a mathematical relationship of proportionality (that is, a linear relationship between two variables).

Nonlinear optics is the study of how intense light interacts with matter. The optical response of a material usually scales linearly with the amplitude of the electric field. At high powers, however, ...