Instability, unpredictability and disorder are very often encountered in natural, technological, ecological, economic and social systems with important consequences on forecasting, design and decision making. These concepts have been historically introduced in the study of the laminar-turbulent transition in fluid flows, where they still represent an active field of research. Some questions of interest in this context are: Why `laminar' solutions, having a maximum degree of symmetry, become unstable and are replaced by less symmetric solutions? What are the reasons of unpredictability in non-linear systems? Is there anything predictable in turbulent flows? The scope of this course is to present our current understanding of these issues.
- Profesor: Josserand Christophe