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arXiv · 2204.01810

Minimal Zero Forcing Sets

Boris Brimkov·Joshua Carlson
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Abstract

In this paper, we study minimal (with respect to inclusion) zero forcing sets. We first investigate when a graph can have polynomially or exponentially many distinct minimal zero forcing sets. We also study the maximum size of a minimal zero forcing set $\overline{\operatorname{Z}}(G)$, and relate it to the zero forcing number $\operatorname{Z}(G)$. Surprisingly, we show that the equality $\overline{\operatorname{Z}}(G)=\operatorname{Z}(G)$ is preserved by deleting a universal vertex, but not by adding a universal vertex. We also characterize graphs with extreme values of $\overline{\operatorname{Z}}(G)$ and explore the gap between $\overline{\operatorname{Z}}(G)$ and $\operatorname{Z}(G)$.

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Boris Brimkov, Joshua Carlson. 2022-04-04. Minimal Zero Forcing Sets. https://arxiv.org/abs/2204.01810

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