English

The Maker-Breaker percolation game on a random board

Probability 2024-02-28 v1 Combinatorics

Abstract

The (m,b)(m,b) Maker-Breaker percolation game on (Z2)p(\mathbb{Z}^2)_p, introduced by Day and Falgas-Ravry, is played in the following way. Before the game starts, each edge of Z2\mathbb{Z}^2 is removed independently with probability 1p1-p. After that, Maker chooses a vertex v0v_0 to protect. Then, in each round Maker and Breaker claim respectively mm and bb unclaimed edges of GG. Breaker wins if after the removal of the edges claimed by him the component of v0v_0 becomes finite, and Maker wins if she can indefinitely prevent Breaker from winning. We show that for any p<1p < 1, Breaker almost surely has a wining strategy for the (1,1)(1,1) game on (Z2)p(\mathbb{Z}^2)_p. This fully answers a question of Day and Falgas-Ravry, who showed that for p=1p = 1 Maker has a winning strategy for the (1,1)(1,1) game. Further, we show that in the (2,1)(2,1) game on (Z2)p(\mathbb{Z}^2)_p Maker almost surely has a winning strategy whenever p>0.9402p > 0.9402, while Breaker almost surely has a winning strategy whenever p<0.5278p < 0.5278. This shows that the threshold value of pp above which Maker has a winning strategy for the (2,1)(2,1) game on Z2\mathbb{Z}^2 is non-trivial. In fact, we prove similar results in various settings, including other lattices and biases (m,b)(m,b). These results extend also to the most general case, which we introduce, where each edge is given to Maker with probability α\alpha and to Breaker with probability β\beta before the game starts.

Keywords

Cite

@article{arxiv.2402.17547,
  title  = {The Maker-Breaker percolation game on a random board},
  author = {Vojtěch Dvořák and Adva Mond and Victor Souza},
  journal= {arXiv preprint arXiv:2402.17547},
  year   = {2024}
}

Comments

34 pages, 6 figures

R2 v1 2026-06-28T15:02:00.501Z