English

Infinitely many collisions between a recurrent simple random walk and arbitrary many transient random walks in a subballistic random environment

Probability 2025-04-23 v1

Abstract

We consider dd random walks (Sn(j))nN\big(S_n^{(j)}\big)_{n\in\mathbb{N}}, 1jd1\leq j \leq d, in the same random environment ω\omega in Z\mathbb{Z}, and a recurrent simple random walk (Zn)nN(Z_n)_{n\in\mathbb{N}} on Z\mathbb{Z}. We assume that, conditionally on the environment ω\omega, all the random walks are independent and start from even initial locations. Our assumption on the law of the environment is such that a single random walk in the environment ω\omega is transient to the right but subballistic, with parameter 0<κ<1/20<\kappa<1/2. We show that - for every value of dd - there are almost surely infinitely many times for which all these random walks, (Zn)nN(Z_n)_{n\in\mathbb{N}} and (Sn(j))nN\big(S_n^{(j)}\big)_{n\in\mathbb{N}}, 1jd1\leq j \leq d, are simultaneously at the same location, even though one of them is recurrent and the dd others ones are transient.

Keywords

Cite

@article{arxiv.2504.15999,
  title  = {Infinitely many collisions between a recurrent simple random walk and arbitrary many transient random walks in a subballistic random environment},
  author = {Alexis Devulder},
  journal= {arXiv preprint arXiv:2504.15999},
  year   = {2025}
}

Comments

11 pages ; applying and extending some results of arXiv:1811.12763 ; to appear in Electronic Communications in Probability