Non-linear Instabilities
  Wave resonance is the fundamental mechanism of non-linear instabilities of fluid flows, and affects the long-time evolution of fluid motions and other physical problems described by non-linear differential equations. Some significant consequences, not well known and completely different from linear instabilities, are summarized in this paper from the studies of past two decades. 
Lun-Shin Yao (Arizona State University)
math-ph math.MP