arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1311.2199math.PR
收藏

半离散半线性抛物型随机偏微分方程

Semi-discrete semi-linear parabolic SPDEs

Nicos Georgiou, Mathew Joseph, Davar Khoshnevisan, Shang-Yuan Shiu

摘要:

考虑一个相互作用的伊藤扩散的无限大系统\[\partial_tu_t(x)=(\mathscr{L}u_t)(x)+ σ\bigl(u_t(x)\bigr)\partial_tB_t(x)\],它起始于一个非负的确定性有界初始轮廓。我们研究了非线性$σ$在标准正则性假设下解的局部和全局特征。我们将证明,在局部时间,解决方案的行为作为一个独立的扩散的集合。证明了连续空间随机热方程的$k$阶矩李雅普诺夫指数经常是尖阶的$k^2$,而连续空间随机热方程的$k$阶矩李雅普诺夫指数可以是尖阶的$k^3$ .当潜在的步行是瞬态的和噪声水平是足够低的,我们也证明了解决方案是a.s.假设初始分布在$\ell^1(\mathbf {Z}^d)$中,则均匀耗散。

英文摘要:

Consider an infinite system \[\partial_tu_t(x)=(\mathscr{L}u_t)(x)+ σ\bigl(u_t(x)\bigr)\partial_tB_t(x)\] of interacting Itô diffusions, started at a nonnegative deterministic bounded initial profile. We study local and global features of the solution under standard regularity assumptions on the nonlinearity $σ$. We will show that, locally in time, the solution behaves as a collection of independent diffusions. We prove also that the $k$th moment Lyapunov exponent is frequently of sharp order $k^2$, in contrast to the continuous-space stochastic heat equation whose $k$th moment Lyapunov exponent can be of sharp order $k^3$. When the underlying walk is transient and the noise level is sufficiently low, we prove also that the solution is a.s. uniformly dissipative provided that the initial profile is in $\ell^1(\mathbf {Z}^d)$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑