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arXiv · 2008.06552

On leaky forcing and resilience

Joseph S. Alameda·Jürgen Kritschgau·Nathan Warnberg·Michael Young
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Abstract

A leak is a vertex that is not allowed to perform a force during the zero forcing process. Leaky forcing was recently introduced as a new variation of zero forcing in order to analyze how leaks in a network disrupt the zero forcing process. The $\ell$-leaky forcing number of a graph is the size of the smallest zero forcing set that can force a graph despite $\ell$ leaks. A graph $G$ is $\ell$-resilient if its zero forcing number is the same as its $\ell$-leaky forcing number. In this paper, we analyze $\ell$-leaky forcing and show that if an $(\ell-1)$-leaky forcing set $B$ is robust enough, then $B$ is an $\ell$-leaky forcing set. This provides the framework for characterizing $\ell$-leaky forcing sets. Furthermore, we consider structural implications of $\ell$-resilient graphs. We apply these results to bound the $\ell$-leaky forcing number of several graph families including trees, supertriangles, and grid graphs. In particular, we resolve a question posed by Dillman and Kenter concerning the upper bound on the $1$-leaky forcing number of grid graphs.

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Joseph S. Alameda, Jürgen Kritschgau, Nathan Warnberg, Michael Young. 2020-08-14. On leaky forcing and resilience. https://arxiv.org/abs/2008.06552

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