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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
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- Partitioning the club guessing January 22, 2014

### Keywords

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

# Tag Archives: projective 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