Tomasz Żuchowski: Tukey types of orthogonal ideals
08/05/15 08:24
Tuesday, May 12, 2015 17:15
Room: D1-215
Speaker: Tomasz Żuchowski
Title: Tukey types of orthogonal ideals
Abstract. A partial order \(P\) is Tukey reducible to partial order \(Q\) when there exists a function \(f:P\to Q\) such that if \(A\) is a bounded subset of \(Q\) then \(f^{-1}[A]\) is a bounded subset of \(P\). The existence of such reduction is related to some cardinal invariants of considered orders. We will show Tukey reductions between some special ideals of subsets of \(\mathbb{N}\) with the inclusion order and other partial orders.
Room: D1-215
Speaker: Tomasz Żuchowski
Title: Tukey types of orthogonal ideals
Abstract. A partial order \(P\) is Tukey reducible to partial order \(Q\) when there exists a function \(f:P\to Q\) such that if \(A\) is a bounded subset of \(Q\) then \(f^{-1}[A]\) is a bounded subset of \(P\). The existence of such reduction is related to some cardinal invariants of considered orders. We will show Tukey reductions between some special ideals of subsets of \(\mathbb{N}\) with the inclusion order and other partial orders.