Heriot-Watt Mathematics Report Series
HWM00-3, 3 March 2000

Stochastic dissipative PDE's and Gibbs measures

S B Kuksin and A Shirikyan


Abstract

\begin{abstract} We study a class of dissipative nonlinear PDE's forced by a random force $\eta^\omega(t,x)$, with the space variable~$x$ varying in a bounded domain. The class contains the 2D Navier-Stokes equations (under periodic or Dirichlet boundary conditions), and the forces we consider are those common in statistical hydrodynamics: they are random fields smooth in~$x$ and stationary, short-correlated in time~$t$. In this paper, we confine ourselves to ``kick forces'' of the form $$ \eta^\omega(t,x)=\sum_{k=-\infty}^{+\infty}\delta(t-kT)\eta_k(x), $$ where the $\eta_k$'s are smooth bounded identically distributed random fields. The equation in question defines a Markov chain in an appropriately chosen phase space (a subset of a function space) that contains the zero function and is invariant for the (random) flow of the equation. Concerning this Markov chain, we prove the following main result (see Theorem~\ref{t2.2}): The Markov chain has a unique invariant measure}. To prove this theorem, we present a construction assigning, to any invariant measure, a Gibbs measure for a~1D system with compact phase space and apply a version of Ruelle-Perron-Frobenius uniqueness theorem to the corresponding Gibbs system. We also discuss ergodic properties of the invariant measure and corresponding properties of the original randomly forced PDE. \end{abstract}

Google Scholar Search: links, citations and journal (if available)

Full text: http://www.ma.hw.ac.uk/~kuksin/

Publication

S B Kuksin, A N Smith , Stochastic dissipative PDE's and Gibbs measures, Communications in Mathematical Physics, 213, 291-330, (2000).


Contact Details | 2000 Reports Index | Full Index