On weak convergence of stochastic wave equation with colored noise on $\mathbb{R}$

Wenxuan Tao

Published 2024-08-19Version 1

In this paper, we study the following stochastic wave equation on the real line $\partial_t^2 u_{\alpha}=\partial_x^2 u_{\alpha}+b\left(u_\alpha\right)+\sigma\left(u_\alpha\right)\eta_{\alpha}$. The noise $\eta_\alpha$ is white in time and colored in space with covariance structure $\mathbb{E}[\eta_\alpha(t,x)\eta_\alpha(s,y)]=\delta(t-s)f_\alpha(x-y)$ where $f_\alpha(x)\propto |x|^{-\alpha}$ is the Riesz kernel. We state the continuity of the solution $u_\alpha$ in terms of $\alpha$ for $\alpha\in (0,1)$ with respect to the convergence in law in the topology of continuous functions with uniform metric on compact sets. We also prove that the probability measure induced by $u_\alpha$ converges weakly to the one induced by the solution in the space-time white noise case as $\alpha$ goes to $1$.