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arXiv · 1211.2473

Poset limits can be totally ordered

Jan Hladky·Andras Mathe·Viresh Patel·Oleg Pikhurko
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Abstract

S.Janson [Poset limits and exchangeable random posets, Combinatorica 31 (2011), 529--563] defined limits of finite posets in parallel to the emerging theory of limits of dense graphs. We prove that each poset limit can be represented as a kernel on the unit interval with the standard order, thus answering an open question of Janson. We provide two proofs: real-analytic and combinatorial. The combinatorial proof is based on a Szemeredi-type Regularity Lemma for posets which may be of independent interest. Also, as a by-product of the analytic proof, we show that every atomless ordered probability space admits a measure-preserving and almost order-preserving map to the unit interval.

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Jan Hladky, Andras Mathe, Viresh Patel, Oleg Pikhurko. 2013-11-04. Poset limits can be totally ordered. https://arxiv.org/abs/1211.2473

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