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- Prikry forcing may add a Souslin tree June 12, 2016
- The reflection principle $R_2$ May 20, 2016
- Prolific Souslin trees March 17, 2016
- Genearlizations of Martin’s Axiom and the well-met condition January 11, 2015
- Many diamonds from just one January 6, 2015
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- Partitioning the club guessing January 22, 2014

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11P99 weak square Rado's conjecture Rock n' Roll HOD Large Cardinals xbox Slim tree Ascent Path Constructible Universe reflection principles polarized partition relation Club Guessing stationary reflection Foundations Hindman's Theorem Uniformization sap Absoluteness square Partition Relations Almost Souslin Singular cardinals combinatorics Whitehead Problem Cardinal function Singular Cofinality Cohen real 20M14 Chromatic number Aronszajn tree diamond star Dushnik-Miller Mandelbrot set Martin's Axiom Hedetniemi's conjecture weak diamond Minimal Walks OCA Non-saturation Prikry-type forcing Souslin Tree Antichain Erdos Cardinal Coherent tree Sakurai's Bell inequality Fast club approachability ideal tensor product graph Poset Successor of Singular Cardinal Almost-disjoint famiy Singular Density very good scale Knaster b-scale Square-Brackets Partition Relations Fat stationary set Fodor-type reflection Ostaszewski square L-space Rainbow sets Prevalent singular cardinals free Boolean algebra Hereditarily Lindelöf space Axiom R Singular coﬁnality coloring number projective Boolean algebra PFA(S)[S] 05A17 Reduced Power P-Ideal Dichotomy Chang's conjecture ccc Jonsson cardinal Forcing middle diamond Universal Sequences Almost countably chromatic Cardinal Invariants Diamond Weakly compact cardinal Kurepa Hypothesis Commutative cancellative semigroups Successor of Regular Cardinal Microscopic Approach 05D10 Generalized Clubs S-Space Small forcing incompactness stationary hitting Selective Ultrafilter Shelah's Strong Hypothesis Erdos-Hajnal graphs Parameterized proxy principle Forcing Axioms Stevo Todorcevic PFA

# Tag Archives: free Boolean algebra

## 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