## Annals of Probability

### A lower bound for disconnection by simple random walk

Xinyi Li

#### Abstract

We consider simple random walk on $\mathbb{Z}^{d}$, $d\geq3$. Motivated by the work of A.-S. Sznitman and the author in [Probab. Theory Related Fields 161 (2015) 309–350] and [Electron. J. Probab. 19 (2014) 1–26], we investigate the asymptotic behavior of the probability that a large body gets disconnected from infinity by the set of points visited by a simple random walk. We derive asymptotic lower bounds that bring into play random interlacements. Although open at the moment, some of the lower bounds we obtain possibly match the asymptotic upper bounds recently obtained in [Disconnection, random walks, and random interlacements (2014)]. This potentially yields special significance to the tilted walks that we use in this work, and to the strategy that we employ to implement disconnection.

#### Article information

Source
Ann. Probab., Volume 45, Number 2 (2017), 879-931.

Dates
Revised: September 2015
First available in Project Euclid: 31 March 2017

https://projecteuclid.org/euclid.aop/1490947310

Digital Object Identifier
doi:10.1214/15-AOP1077

Mathematical Reviews number (MathSciNet)
MR3630289

Zentralblatt MATH identifier
06797082

#### Citation

Li, Xinyi. A lower bound for disconnection by simple random walk. Ann. Probab. 45 (2017), no. 2, 879--931. doi:10.1214/15-AOP1077. https://projecteuclid.org/euclid.aop/1490947310

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