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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

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

# Tag Archives: Fodor-type reflection

## 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

## Openly generated Boolean algebras and the Fodor-type reflection principle

Joint work with Sakaé Fuchino. Abstract: We prove that the Fodor-type Reflection Principle (FRP) is equivalent to the assertion that any Boolean algebra is openly generated if and only if it is $\aleph _2$-projective. Previously it was known that this … Continue reading