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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

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

# Tag Archives: 03G05

## 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