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- A strong form of König’s lemma October 21, 2017
- Prikry forcing may add a Souslin tree June 12, 2016
- The reflection principle $R_2$ May 20, 2016
- Prolific Souslin trees March 17, 2016
- Generalizations of Martin’s Axiom and the well-met condition January 11, 2015
- Many diamonds from just one January 6, 2015
- Happy new jewish year! September 24, 2014
- Square principles April 19, 2014

### Keywords

Ostaszewski square Microscopic Approach Erdos-Hajnal graphs tensor product graph Stevo Todorcevic Chromatic number 20M14 Forcing Club Guessing Aronszajn tree Rado's conjecture Hedetniemi's conjecture square principles ccc middle diamond HOD Almost-disjoint famiy weak diamond PFA Poset Distributive tree Mandelbrot set Successor of Regular Cardinal b-scale Uniformization Shelah's Strong Hypothesis Selective Ultrafilter Martin's Axiom Singular Density Parameterized proxy principle Axiom R Whitehead Problem Hereditarily Lindelöf space L-space Hindman's Theorem Cardinal function Absoluteness Square-Brackets Partition Relations Reduced Power Large Cardinals Ascent Path Antichain Foundations Dushnik-Miller Prevalent singular cardinals stationary reflection Constructible Universe Universal Sequences Commutative cancellative semigroups Uniformly coherent Fodor-type reflection Singular coﬁnality OCA Postprocessing function polarized partition relation Non-saturation Almost Souslin Diamond Successor of Singular Cardinal Small forcing Luzin set Nonspecial tree Minimal Walks Slim tree weak square Rainbow sets S-Space stationary hitting 05A17 Cardinal Invariants Souslin Tree free Boolean algebra reflection principles Jonsson cardinal square Kurepa Hypothesis Almost countably chromatic Rock n' Roll incompactness Partition Relations diamond star sap very good scale Fat stationary set approachability ideal Cohen real Chang's conjecture Forcing Axioms coloring number PFA(S)[S] Fast club super-Souslin tree Singular cardinals combinatorics Generalized Clubs Knaster 11P99 projective Boolean algebra P-Ideal Dichotomy Weakly compact cardinal Prikry-type forcing Coherent tree Erdos Cardinal Sakurai's Bell inequality xbox

# Tag Archives: coloring number

## MFO workshop in Set Theory, February 2017

I gave an invited talk at the Set Theory workshop in Obwerwolfach, February 2017. Talk Title: Coloring vs. Chromatic. Abstract: In a joint work with Chris Lambie-Hanson, we study the interaction between compactness for the chromatic number (of graphs) and … Continue reading

Posted in Invited Talks
Tagged Chromatic number, coloring number, incompactness, stationary reflection
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## Reflection on the coloring and chromatic numbers

Joint work with Chris Lambie-Hanson. Abstract. We prove that reflection of the coloring number of graphs is consistent with non-reflection of the chromatic number. Moreover, it is proved that incompactness for the chromatic number of graphs (with arbitrarily large gaps) … Continue reading