Nonlinear differential or difference equations are encountered not only in mathematics, but also in many areas of physics (evolution equations, propagation of a signal in an optical fiber), chemistry (reaction-diffusion systems), and biology (competition of species).
This book introduces the reader to methods allowing one to build explicit solutions to these equations. A prerequisite task is to investigate whether the chances of success are high or low, and this can be achieved without any a priori knowledge of the solutions, with a powerful algorithm presented in detail called the Painlevé test. If the equation under study passes the Painlevé test, the equation is presumed integrable. If on the contrary the test fails, the system is nonintegrable or even chaotic, but it may still be possible to find solutions.
The examples chosen to illustrate these methods are mostly taken from physics. These include on the integrable side the nonlinear Schrödinger equation (continuous and discrete), the Korteweg-de Vries equation, the Hénon-Heiles Hamiltonians, on the nonintegrable side the complex Ginzburg-Landau equation (encountered in optical fibers, turbulence, etc), the Kuramoto-Sivashinsky equation (phase turbulence), the Kolmogorov-Petrovski-Piskunov equation (KPP, a reaction-diffusion model), the Lorenz model of atmospheric circulation and the Bianchi IX cosmological model.
Written at a graduate level, the book contains tutorial text as well as detailed examples and the state of the art on some current research.
About the Author: Robert Conte is associate director of research at the Centre de mathématiques et de leurs applications, École normale supérieure de Cachan, CNRS, Université Paris-Saclay. He is also an honorary professor in the Department of Mathematics at the University of Hong Kong, and an associate external member of the Centre de recherches mathématiques, Université de Montréal, Canada. He received his PhD from Université Paris VI and held positions at IBM France, UC Berkeley, and the Commissariat à l'énergie atomique, Saclay, before taking on his current role. He has co-authored and edited six books and published nearly 100 articles in refereed journals. Trained in both mathematics and physics, the main theme of his research is the mathematical solution of theoretical problems arising from physics.
Micheline Musette is professor emerita at the Vrije Universiteit, Dienst Theoretische Natuurkunde (TENA) Brussels, Belgium. Prior to joining the Vrije Universiteit, she completed a PhD at Université Libre, Brussels, and held positions at the Inter University Institute for Nuclear Sciences and the National Fund for Scientific Research, Belgium. She has published around 60 papers in refereed journals, and is a member of the American Physical Society.
