Recent and upcoming talks by Chris Lambie-Hanson

Chris Lambie-Hanson: Constructions from square and diamond, with an application to super-Souslin trees

Monday, May 8, 2017, 16.30 Seminar room 0.011, Mathematical Institute, University of Bonn Speaker: Chris Lambie-Hanson (Bar-Ilan) Title: Constructions from square and diamond, with an application to super-Souslin trees Abstract. In 1982, Shelah and Stanley proved that, if $\kappa$ is a regular, infinite cardinal, $2^\kappa = \kappa^+$, and there is a $(\kappa^+, 1)$-morass, then there is a $\kappa^{++}$-super-Souslin tree, which is a type of normal $\kappa^{++}$-tree that necessarily has a $\kappa^{++}$-Souslin subtree and continues to do so in any outer model in which $\kappa^{++}$ is preserved and no new subsets of $\kappa$ are present. continue reading…

Chris Lambie-Hanson: Partition relations and generalized scattered orders

BIU seminar in Set Theory On 30/03/2017, 10-12, Building 604, Room 103 Speaker: Chris Lambie-Hanson Title: Partition relations and generalized scattered orders Abstract: The class of scattered linear orders, isolated by Hausdorff, plays a prominent role in the study of general linear orders. continue reading…

Chris Lambie-Hanson: Trees with ascent paths

HUJI Logic Seminar  The next meeting of the Logic Seminar will be in Wednesday, 22/03/17, 16:00 – 18:00, Ross buiding. Speaker: Chris Lambie-Hanson Title: Reflections on the coloring and chromatic numbers Abstract: The notion of an ascent path through a tree, isolated by Laver, is a generalization of the notion of a cofinal branch and, in many cases, the existence of an ascent path through a tree provides a concrete obstruction to the tree being special. continue reading…

Chris Lambie-Hanson: Reflections on the coloring and chromatic numbers

HUJI Logic Seminar  The next meeting of the Logic Seminar will be in Wednesday, 18/01, 16:00 – 18:00, Ross 70. Speaker: Chris Lambie-Hanson Title: Reflections on the coloring and chromatic numbers Abstract: Compactness phenomena play a central role in modern set theory, and the investigation of compactness and incompactness for the coloring and chromatic numbers of graphs has been a thriving area of research since the mid-20th century,when De Bruijn and Erdős published their compactness theorem for finite chromatic numbers. continue reading…

2016 Graduate summer school in set theory, Irvine, July 25 – August 5 2016

A graduate summer school in set theory will be held July 25 – August 5 2016 at the University of California Irvine. The subject of the summer school will be singular cardinal combinatorics, with a focus on PCF theory. continue reading…

Chris Lambie-Hanson: Coloring classes and the Hanf number for amalgamation.

Set Theory and Topology seminar (BGU)  Notice the one-time change in place to +201. Time: Tuesday, March 24, 12:15-13:40. Place: Seminar room +201, Math building 58. Speaker: Chris Lambie-Hanson (HUJI). Title: Coloring classes and the Hanf number for amalgamation. continue reading…

Chris Lambie-Hanson: Bounded Stationary Reflection

Students Set Theory Seminar (HUJI) We shall meet Wednesday (December 10) in the Hebrew University (in Ross 70), 14:45-16:00. Speaker: Chris Lambie-Hanson Title: Bounded Stationary Reflection Abstract: Eisworth, motivated in part by his work on square-bracket partition relations, asked whether it must be the case that if mu is a singular cardinal and every stationary subset of mu^+ reflects, then every stationary subset of mu^+ reflects at an ordinal of arbitrarily high cofinality below mu. continue reading…

Chris Lambie-Hanson: Well-colorings and the Hanf number for amalgamation

Infinite Combinatorics Seminar (BIU) 9/November/2014, 10-12, Room 201, Building 216, Bar-Ilan University Speaker: Chris Lambie-Hanson (HUJI) Title: Well-colorings and the Hanf number for amalgamation Abstract: The amalgamation property is a topic of fundamental interest in model theory and is still imperfectly understood. continue reading…

Winter School, Jan 31 – Feb 7, 2015

We are pleased to announce that the registration for the Winter School in Abstract Analysis, section Set Theory & Topology is now open. The conference will take place between Jan 31st and Feb 7th 2015 in Hejnice, Czech Republic. continue reading…

Chris Lambie-Hanson: Jónsson cardinals, partition relations, and stationary reflection, Part III

Speaker:  Chris Lambie-Hanson Title: Jónsson cardinals, partition relations, and stationary reflection, Part III Abstract: I will present a proof that, relative to large cardinal assumptions, it is consistent that there is a singular cardinal mu such that every stationary subset of mu^+ reflects but that there is a stationary subset of mu^+ that does not reflect at ordinals of arbitrarily high cofinality. continue reading…