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Events by date

Thursday, March 18, 2021

Thursday, March 18, 2021 — 1:00 PM EDT

Title: The Poset Conjecture: results, counterexamples, and open problems

Speaker: David Wagner Affiliation: University of Waterloo Zoom: Contact Karen Yeats

Abstract:

In 1978, Neggers conjectured that a certain transform of the order polynomial of a partially ordered set (poset) has only real roots.

In the late 1980s, Stanley gave this to me as a thesis project, generalized to labelled posets.  For my thesis I proved the conclusion for series-parallel labelled posets and a bit more.  Br\"and\'en, and later Stembridge, found counterexamples to the conjecture in general.

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