Flows Without Pressure, Geometry and Turbulence
Speaker:
Andrei Biryuk, Kuban State University and The Fields Institute
Date and Time:
Saturday, January 31, 2004 - 5:00pm to 5:30pm
Location:
Fields Institute, Room 230
Abstract:
We start with the Cauchy problem for the multidimensional Burgers type equation with periodic boundary conditions. We introduce the notion of degeneracy for vector fields. Vector field $u$ is degenerate iff one of the following equivalent conditions holds: (*) the Jacoby matrix of $u$ is everywhere nilpotent (*) the pressureless Euler equation with the initial state $u$ is globally solvable in the class of $C1$-continuous functions. Non-degenerate initial states develops large spatial derivatives (turbulence). In 2D there is a nice geometric criterion for degeneracy due to Pogorelov cylinder theorem.