Competition on $\mathbb{Z}^d$ driven by branching random walk

Maria Deijfen; Timo Vilkas

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arXiv · 2203.14166

Competition on $\mathbb{Z}^d$ driven by branching random walk

Maria Deijfen·Timo Vilkas

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Abstract

A competition process on $\mathbb{Z}^d$ is considered, where two species compete to color the sites. The entities are driven by branching random walks. Specifically red (blue) particles reproduce in discrete time and place offspring according to a given reproduction law, which may be different for the two types. When a red (blue) particle is placed at a site that has not been occupied by any particle before, the site is colored red (blue) and keeps this color forever. The types interact in that, when a particle is placed at a site of opposite color, the particle adopts the color of the site with probability $p\in[0,1]$. Can a given type color infinitely many sites? Can both types color infinitely many sites simultaneously? Partial answers are given to these questions and many open problems are formulated.

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Maria Deijfen, Timo Vilkas. 2022-03-26. Competition on $\mathbb{Z}^d$ driven by branching random walk. https://arxiv.org/abs/2203.14166

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