# Borisa Kuzeljevic: A long chain of P-points

Invitation to the Logic Seminar at the National University of Singapore

Date: Wednesday, 6 April 2016, 17:00 hrs

Room: S17#05-11, Department of Mathematics, NUS

Speaker: Borisa Kuzeljevic

Title: A long chain of P-points

URL: http://www.comp.nus.edu.sg/~fstephan/logicseminar.html

Abstract:
We will construct, under CH, a sequence of P-points
{U_alpha: alpha < omega_2} in such a way that for every
alpha, beta with alpha < beta < omega_2
the ultrafilter U_alpha is Rudin-Keisler reducible to U_beta
while the ultrafilter U_beta is not Tukey reducible to U_alpha.

Joint work with: Dilip Raghavan