# Tomasz Żuchowski: Tukey types of orthogonal ideals

Tuesday, May 12, 2015, 17:15
Wrocław University of Technology, 215 D-1

Speaker: Tomasz Żuchowski (University of Wroclaw)

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->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 N with the inclusion order and other partial orders.