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### Recent blog posts

- 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
- Partitioning the club guessing January 22, 2014

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

# 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