English

Density behaviour related to L\'evy processes

Probability 2019-12-10 v1

Abstract

Let pt(x)p_t(x), ft(x)f_t(x) and qt(x)q_t^*(x) be the densities at time tt of a real L\'evy process, its running supremum and the entrance law of the reflected excursions at the infimum. We provide relationships between the asymptotic behaviour of pt(x)p_t(x), ft(x)f_t(x) and qt(x)q_t^*(x), when tt is small and xx is large. Then for large xx, these asymptotic behaviours are compared to this of the density of the L\'evy measure. We show in particular that, under mild conditions, if pt(x)p_t(x) is comparable to tν(x)t\nu(x), as t0t\rightarrow0 and xx\rightarrow\infty, then so is ft(x)f_t(x).

Keywords

Cite

@article{arxiv.1912.04193,
  title  = {Density behaviour related to L\'evy processes},
  author = {Loïc Chaumont and Jacek Małecki},
  journal= {arXiv preprint arXiv:1912.04193},
  year   = {2019}
}

Comments

25 pages

R2 v1 2026-06-23T12:40:19.272Z