Hitting time for loose Hamilton cycles in the random hypergraph process

Jared León; Xizhi Liu

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arXiv · 2610.29894

Hitting time for loose Hamilton cycles in the random hypergraph process

Jared León·Xizhi Liu

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Abstract

The random hypergraph process starts with an empty hypergraph on $n$ vertices and adds a uniformly chosen missing edge at each step. For even $n$, we prove that, with high probability, a $3$-uniform loose Hamilton cycle appears when the last isolated vertex disappears. The approach developed here adapts arguments from Kahn's work on perfect matchings. It can also be extended to obtain the corresponding hitting-time theorems for $r=2$ and every fixed $r\ge4$ satisfying $(r-1)\mid n$. Furthermore, it can be used to estimate the numbers of loose Hamilton cycles at these hitting times for every fixed $r\ge2$, up to a factor of $\exp\{o(n)\}$.

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Jared León, Xizhi Liu. 2026-10-21. Hitting time for loose Hamilton cycles in the random hypergraph process. https://arxiv.org/abs/2610.29894

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