02.10.17 - Steve Tobias is Professor of Applied Mathematics at the University of Leeds. Having completed his PhD in DAMTP, Cambridge on "Nonlinear Solar and Stellar Dynamos" in 1995, he has been a Research Fellow of Trinity College Cambridge (1995-2000), a Research Associate of JILA, University of Colorado (1996-1998) and a Lecturer, Reader and Professor at the University of Leeds. His interests include nonlinear fluid dynamics (including magnetohydrodynamics) and its applications in experiments, geophysics and astrophysics via the application of methods from nonlinear dynamics and statistical physics.
The eleven year solar activity cycle is a remarkable example of regular behaviour emerging from an extremely turbulent system. The jets on Jupiter sit unmoving on a sea of turbulent eddies. Systematic flows emerge from the interaction of eddies in experiments, engineering and geophysics. Phenomena in astrophysics and engineering often display organisation on spatial and temporal scales much larger than the turbulent processes that drive them.
An outstanding problem of astrophysics (and indeed other branches of nonlinear physics) is how to describe the statistics of systematic behaviour emerging from the underlying chaos, given that Direct Numerical Simulation of these objects is simply impossible. Here I shall introduce these fascinating phenomena and describe how methods from non-equilibrium statistical mechanics and many body quantum systems may be developed to give some insight into their behaviour.