Title 
Controlling statistical properties in simulations of extended
dynamical systems

Abstract. Many complex dynamical systems are subject to uncertainty in
the initial data, chaotic internal mixing, and unresolved interactions
with an environment. For these reasons a statistical perspective is
often taken: trajectories are treated as tools for computing averages
with respect to some statistical ensemble (defined by a suitable phase
space density, typically a function of the energy). I will discuss
methods for performing such calculations based on a flexible family of
stochastic-dynamical systems. These techniques are most commonly used
in molecular simulation to control temperature or pressure, but there
are many possibilities for their introduction in other applications. I
will discuss an example involving a point-vortex model of a fluid as
considered by Onsager.