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arXiv · 1903.05052

Dirac's theorem for random regular graphs

Padraig Condon·Alberto Espuny Díaz·António Girão·Daniela Kühn·Deryk Osthus
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Abstract

We prove a `resilience' version of Dirac's theorem in the setting of random regular graphs. More precisely, we show that, whenever $d$ is sufficiently large compared to $\varepsilon>0$, a.a.s. the following holds: let $G'$ be any subgraph of the random $n$-vertex $d$-regular graph $G_{n,d}$ with minimum degree at least $(1/2+\varepsilon)d$. Then $G'$ is Hamiltonian. This proves a conjecture of Ben-Shimon, Krivelevich and Sudakov. Our result is best possible: firstly, the condition that $d$ is large cannot be omitted, and secondly, the minimum degree bound cannot be improved.

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Padraig Condon, Alberto Espuny Díaz, António Girão, Daniela Kühn, Deryk Osthus. 2019-03-12. Dirac's theorem for random regular graphs. https://arxiv.org/abs/1903.05052

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