English

Asymptotics of returns to the coordinate hyperplanes for conditioned simple random walks

Probability 2025-12-24 v1 Combinatorics

Abstract

In this paper we study the number of returns to the coordinate hyperplanes for multidimensional nearest-neighbour random walks. While one-dimensional results on returns are classical, much less is known in higher dimensions. We analyse the asymptotic behaviour of returns under several natural conditionings: the unconditioned walk, bridges, meanders, and non-negative bridges (or excursions). Our main results characterize the limiting distributions under appropriate rescaling. The resulting one-dimensional marginals may be half-normal, Rayleigh, geometric, negative binomial, or certain mixtures thereof. In most situations, the coordinates are asymptotically independent; however, there are notable exceptions for the meander case, depending on the drift. The proofs rely on conditioning on the numbers of horizontal and vertical steps, which restores a form of independence and reduces the problem to one-dimensional estimates via binomial convolution and Bernstein-type approximations.

Keywords

Cite

@article{arxiv.2512.19822,
  title  = {Asymptotics of returns to the coordinate hyperplanes for conditioned simple random walks},
  author = {Rodolphe Garbit and Kilian Raschel},
  journal= {arXiv preprint arXiv:2512.19822},
  year   = {2025}
}

Comments

29 pages, 3 figures