English

On slowdown and speedup of transient random walks in random environment

Probability 2012-01-31 v3

Abstract

We consider one-dimensional random walks in random environment which are transient to the right. Our main interest is in the study of the sub-ballistic regime, where at time nn the particle is typically at a distance of order O(nκ)O(n^\kappa) from the origin, κ(0,1)\kappa\in(0,1). We investigate the probabilities of moderate deviations from this behaviour. Specifically, we are interested in quenched and annealed probabilities of slowdown (at time nn, the particle is at a distance of order O(nν0)O(n^{\nu_0}) from the origin, ν0(0,κ)\nu_0\in (0,\kappa)), and speedup (at time nn, the particle is at a distance of order nν1n^{\nu_1} from the origin, ν1(κ,1)\nu_1\in (\kappa,1)), for the current location of the particle and for the hitting times. Also, we study probabilities of backtracking: at time nn, the particle is located around (nν)(-n^\nu), thus making an unusual excursion to the left. For the slowdown, our results are valid in the ballistic case as well.

Keywords

Cite

@article{arxiv.0806.0790,
  title  = {On slowdown and speedup of transient random walks in random environment},
  author = {Alexander Fribergh and Nina Gantert and Serguei Popov},
  journal= {arXiv preprint arXiv:0806.0790},
  year   = {2012}
}

Comments

43 pages, 4 figures; to appear in Probability Theory and Related Fields