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Towards the 0-statement of the Kohayakawa-Kreuter conjecture

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 نشر من قبل Joseph Hyde
 تاريخ النشر 2021
  مجال البحث
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 تأليف Joseph Hyde




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In this paper, we study asymmetric Ramsey properties of the random graph $G_{n,p}$. Let $r in mathbb{N}$ and $H_1, ldots, H_r$ be graphs. We write $G_{n,p} to (H_1, ldots, H_r)$ to denote the property that whenever we colour the edges of $G_{n,p}$ with colours from the set $[r] := {1, ldots, r}$ there exists $i in [r]$ and a copy of $H_i$ in $G_{n,p}$ monochromatic in colour $i$. There has been much interest in determining the asymptotic threshold function for this property. R{o}dl and Ruci{n}ski determined the threshold function for the general symmetric case; that is, when $H_1 = cdots = H_r$. A conjecture of Kohayakawa and Kreuter, if true, would fully resolve the asymmetric problem. Recently, the 1-statement of this conjecture was confirmed by Mousset, Nenadov and Samotij. Building on work of Marciniszyn, Skokan, Sp{o}hel and Steger, we reduce the 0-statement of Kohayakawa and Kreuters conjecture to a certain deterministic subproblem. To demonstrate the potential of this approach, we show this subproblem can be resolved for almost all pairs of regular graphs. This therefore resolves the 0-statement for all such pairs of graphs.

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