An edge density exceeding the Turan theorem threshold for by a fixed positive amount forces a balanced subgraph with logarithmic part size. Combine clique supersaturation by sampling with the dense clique family blow-up lemma. Dense binomial random graphs show that the logarithmic order is optimal for a uniform density guarantee.
A fixed positive excess over the Turan theorem threshold forces logarithmic balanced complete multipartite graphs. There is an elementary induction using common neighbourhood from bipartite density: first obtain a logarithmic -partite subgraph from the induction hypothesis, and select disjoint transversal -cliques in it. Each such clique has at least common neighbours, by the union bound on non-neighbour sets. Apply the bipartite common-neighbour count to these cliques as left-side objects. Their selected union and a large common neighbourhood form the extra part.
In a binomial random graph with fixed edge probability below one, the displayed first-moment bound tends to zero for and sufficiently large fixed . At the same time the edge density concentrates near . Thus a positive fixed density cannot force balanced complete multipartite subgraphs whose part size grows faster than logarithmically.
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