Colloquium: Brzezniak -- Stochastic Landau-Lifschitz-Gilbert Equation

This Friday October 9 at 2pm Prof. Zdzislaw Brzezniak (York. U.K.) will speak
at the Joint Colloquium at Sydney Uni.  Details of his talk titled
"Stochastic Landau-Lifschitz-Gilbert Equation" are below.

If you would like to  lunch with the speaker, meet
 outside Carslaw Building at 12.30PM.


___________________JOINT COLLOQUIUM______________________


Speaker:  Prof. Zdzislaw Brzezniak (York. U.K.)

Title:       Stochastic Landau-Lifschitz-Gilbert Equation

Date:      Friday, October 9,  2009
Time:      2:00 pm
Venue:   Room 275 Carslaw Building, University of Sydney

Abstract:  
In this talk we will consider the three-dimensional
Landau-Lifshitz-Gilbert equation perturbed by a
multiplicative space-dependent noise. This equation,
fundamental for the theory of magnetic
memories, describes evolution of spins in ferromagnetic
materials under the influence of thermal
noise. The necessity to include the thermal noise
in the equation was observed by Physicists in the
early fifties but the rigorous mathematical theory
was missing. Since the physical theory prescribes
the fixed length of the spin vectors, any solution
must take values in the sphere. This fact leads
to interesting connections of this equation with
the equation for the flow of harmonic maps. We
show the existence of weak martingale solutions
taking values in a sphere and discuss regularity of
solutions. We will sketch proof of the existence of
solutions and formulate some open problems.
This is a joint work with Ben Goldys and Terry Jegaraj (both UNSW Sydney).







Enquiries to Emma Carberry,carberry@maths.usyd.edu.au, 9351 3796 or
 Brian Jefferies, 0458 8882544, b.jefferies@unsw.edu.au