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arXiv · 2505.04436

Nearly spanning cycle in the percolated hypercube

Michael Anastos·Sahar Diskin·Joshua Erde·Mihyun Kang·Michael Krivelevich·Lyuben Lichev
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Abstract

Let $Q^d$ be the $d$-dimensional binary hypercube. We form a random subgraph $Q^d_p\subseteq Q^d$ by retaining each edge of $Q^d$ independently with probability $p$. We show that, for every constant $\varepsilon>0$, there exists a constant $C=C(\varepsilon)>0$ such that, if $p\ge C/d$, then with high probability $Q^d_p$ contains a cycle of length at least $(1-\varepsilon)2^d$. This confirms a long-standing folklore conjecture, stated in particular by Condon, Espuny D\'iaz, Gir\~ao, K\"uhn, and Osthus [Hamiltonicity of random subgraphs of the hypercube, Mem. Amer. Math. Soc. 305 (2024), No. 1534].

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Michael Anastos, Sahar Diskin, Joshua Erde, Mihyun Kang, Michael Krivelevich, Lyuben Lichev. 2025-05-07. Nearly spanning cycle in the percolated hypercube. https://arxiv.org/abs/2505.04436

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