Exponential mixing for the white-forced complex Ginzburg--Landau equation in the whole space

TL;DR

This paper proves exponential mixing and uniqueness of stationary measures for the white-forced complex Ginzburg--Landau equation on the entire real line, extending ergodic theory to unbounded domains using coupling and weighted estimates.

Contribution

It introduces new techniques to establish ergodic properties of dissipative PDEs on unbounded domains, specifically for the complex Ginzburg--Landau equation with white noise.

Findings

Proved exponential mixing in the dual-Lipschitz metric.

Established uniqueness of stationary measure.

Extended coupling and Foiaș–Prodi estimates to the real line.

Abstract

In the last two decades, there has been a significant progress in the understanding of ergodic properties of white-forced dissipative PDEs. The previous studies mostly focus on equations posed on bounded domains since they rely on different compactness properties and the discreteness of the spectrum of the Laplacian. In the present paper, we consider the damped complex Ginzburg--Landau equation on the real line driven by a white-in-time noise. Under the assumption that the noise is sufficiently non-degenerate, we establish the uniqueness of stationary measure and exponential mixing in the dual-Lipschitz metric. The proof is based on coupling techniques combined with a generalization of Foia\c{s}--Prodi estimate to the case of the real line and special space-time weighted estimates which help to handle the behavior of solutions at infinity.