Random trees with local catastrophes: the Brownian case
Abstract
We introduce and study a model of plane random trees generalizing the famous Bienaym\'e--Galton--Watson model but where births and deaths are locally correlated. More precisely, given a random variable with values in , given the state of the tree at some generation, the next generation is obtained (informally) by successively deleting individuals side-by-side and replacing them with new particles where the samplings are i.i.d. We prove that, in the critical case , and under a third moment condition on and , the random trees coding the genealogy of the population model converges towards the Brownian Continuum Random Tree. Interestingly, our proof does not use the classical height process or the {\L}ukasiewicz exploration, but rather the stochastic flow point of view introduced by Bertoin and Le Gall.
Cite
@article{arxiv.2401.06770,
title = {Random trees with local catastrophes: the Brownian case},
author = {Ariane Carrance and Jérôme Casse and Nicolas Curien},
journal= {arXiv preprint arXiv:2401.06770},
year = {2025}
}
Comments
Updated version with some corrected lemmas, 35 pages, 7 figures