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arXiv 1709.09613math.PR
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首次通过渗流中边界的大小

The size of the boundary in first-passage percolation

Michael Damron, Jack Hanson, Wai-Kit Lam

摘要:

首次通过渗流是使用i.i.d.定义的随机生长模型。在$\mathbb{Z}^d$的最近邻边上的边权重$(t_e)$。初始感染占据了原点并沿着边缘传播,需要时间$t_e$穿过边缘$e$。在本文中,我们研究的感染(“湿”)区域在时间$t$,$B(t)$的边界的大小。已知$B(t)$线性增长,因此其边界$\partial B(t)$具有在$ct^{d-1}$和$Ct^d$之间的大小。在弱矩条件下的权重,我们表明,对于大多数时候,$\partial B(t)$的大小顺序$t^{d-1}$(光滑)。另一方面,对于重尾分布,$B(t)$包含许多小孔,因此,我们表明,$\partial B(t)$的大小顺序$t^{d-1+α}$的一些$α>0$取决于分布。在所有情况下,我们表明,$B(t)$(边缘接触的无界组件的补充$B(t)$)的外边界是光滑的大多数时候。在未证明的关于$B(t)$的极限形状的一致正曲率的假设下,我们证明了对于所有大的$t.$的不等式$\#\partial B(t) \leq (\log t)^C t^{d-1}$

英文摘要:

First-passage percolation is a random growth model defined using i.i.d. edge-weights $(t_e)$ on the nearest-neighbor edges of $\mathbb{Z}^d$. An initial infection occupies the origin and spreads along the edges, taking time $t_e$ to cross the edge $e$. In this paper, we study the size of the boundary of the infected ("wet") region at time $t$, $B(t)$. It is known that $B(t)$ grows linearly, so its boundary $\partial B(t)$ has size between $ct^{d-1}$ and $Ct^d$. Under a weak moment condition on the weights, we show that for most times, $\partial B(t)$ has size of order $t^{d-1}$ (smooth). On the other hand, for heavy-tailed distributions, $B(t)$ contains many small holes, and consequently we show that $\partial B(t)$ has size of order $t^{d-1+α}$ for some $α>0$ depending on the distribution. In all cases, we show that the exterior boundary of $B(t)$ (edges touching the unbounded component of the complement of $B(t)$) is smooth for most times. Under the unproven assumption of uniformly positive curvature on the limit shape for $B(t)$, we show the inequality $\#\partial B(t) \leq (\log t)^C t^{d-1}$ for all large $t.$

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。

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