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- Prikry forcing may add a Souslin tree June 12, 2016
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- Prolific Souslin trees March 17, 2016
- Generalizations of Martin’s Axiom and the well-met condition January 11, 2015
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### Keywords

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

# 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