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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
- 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

### Keywords

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

# 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