arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1901.09449math.PR
收藏

正随机游动与半空间随机偏微分方程的一个恒等式

Positive random walks and an identity for half-space SPDEs

Shalin Parekh

摘要:

本文的目的有三个方面。首先,我们对半空间上的乘性噪声随机热方程引入了一种新的边界条件。这本质上是一个狄利克雷边界条件,但在边界附近有一个非平凡的归一化,这导致了相关混沌序列中的非均匀跃迁密度(大致上,布朗\textit{meander}的跃迁密度)。其次,我们证明了八分圆上的定向聚合物分拆函数对具有这类边界条件的乘性随机热方程的一个新的收敛结果,这又涉及到对上述非齐次马尔可夫过程的详细分析。第三,作为推论,我们证明了半空间上带\textit{different}边界条件的乘性噪声随机热方程的一个令人惊讶的分布相等性。这个恒等式可以看作是证明超临界半空间KPZ在原点处的高斯涨落行为的一个先导。

英文摘要:

The purpose of this article is threefold. First, we introduce a new type of boundary condition for the multiplicative-noise stochastic heat equation on the half space. This is essentially a Dirichlet boundary condition but with a nontrivial normalization near the boundary which leads to inhomogeneous transition densities (roughly, those of a Brownian \textit{meander}) within the associated chaos series. Secondly, we prove a new convergence result of the directed-polymer partition function in an octant to the multiplicative stochastic heat equation with this type of boundary condition, which in turn involves a detailed analysis of the aforementioned inhomogeneous Markov process. Thirdly, as a corollary, we prove a surprising equality-in-distribution for multiplicative-noise stochastic heat equations on the half space with \textit{different} boundary conditions. This identity may be seen as a precursor for proving Gaussian fluctuation behavior of supercritical half-space KPZ at the origin.

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。

↑