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arXiv · 2207.13651

On random irregular subgraphs

Jacob Fox·Sammy Luo·Huy Tuan Pham
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Abstract

Let $G$ be a $d$-regular graph on $n$ vertices. Frieze, Gould, Karoński and Pfender began the study of the following random spanning subgraph model $H=H(G)$. Assign independently to each vertex $v$ of $G$ a uniform random number $x(v) \in [0,1]$, and an edge $(u,v)$ of $G$ is an edge of $H$ if and only if $x(u)+x(v) \geq 1$. Addressing a problem of Alon and Wei, we prove that if $d = o(n/(\log n)^{12})$, then with high probability, for each nonnegative integer $k \leq d$, there are $(1+o(1))n/(d+1)$ vertices of degree $k$ in $H$.

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Jacob Fox, Sammy Luo, Huy Tuan Pham. 2022-07-27. On random irregular subgraphs. https://arxiv.org/abs/2207.13651

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