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arXiv · 0707.0315

How many random edges make a dense hypergraph non-2-colorable?

Benny Sudakov·Jan Vondrak
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Abstract

We study a model of random uniform hypergraphs, where a random instance is obtained by adding random edges to a large hypergraph of a given density. We obtain a tight bound on the number of random edges required to ensure non-2-colorability. We prove that for any k-uniform hypergraph with Omega(n^{k-epsilon}) edges, adding omega(n^{k epsilon/2}) random edges makes the hypergraph almost surely non-2-colorable. This is essentially tight, since there is a 2-colorable hypergraph with Omega(n^{k-ε}) edges which almost surely remains 2-colorable even after adding o(n^{k ε/ 2}) random edges.

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Benny Sudakov, Jan Vondrak. 2007-07-02. How many random edges make a dense hypergraph non-2-colorable?. https://arxiv.org/abs/0707.0315

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