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- Happy new jewish year! September 24, 2014
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- Partitioning the club guessing January 22, 2014
- Walk on countable ordinals: the characteristics December 1, 2013
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### Keywords

Successor of Singular Cardinal reflection principles Cardinal function Ostaszewski square Hereditarily Lindelöf space Whitehead Problem Rainbow sets Erdos Cardinal Successor of Regular Cardinal Knaster Rado's conjecture diamond star Forcing Axioms Cohen real P-Ideal Dichotomy very good scale approachability ideal weak square Weakly compact cardinal stationary reflection Hedetniemi's conjecture Aronszajn tree Dushnik-Miller Axiom R free Boolean algebra PFA Rock n' Roll polarized partition relation Erdos-Hajnal graphs tensor product graph Club Guessing b-scale Martin's Axiom Singular cardinals combinatorics Forcing Poset Almost countably chromatic incompactness Large Cardinals middle diamond Partition Relations Mandelbrot set Kurepa Hypothesis Generalized Clubs Small forcing Prikry-type forcing Singular Density Chromatic number Prevalent singular cardinals Diamond Singular Cofinality S-Space Constructible Universe Non-saturation stationary hitting L-space Minimal Walks OCA sap Antichain Souslin Tree PFA(S)[S] Almost-disjoint famiy projective Boolean algebra weak diamond square Uniformization Foundations Square-Brackets Partition Relations Cardinal Invariants Sakurai's Bell inequality ccc Universal Sequences Absoluteness Shelah's Strong Hypothesis

# Tag Archives: 03E55

## 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

## On the consistency strength of the Milner-Sauer conjecture

Abstract: In their paper from 1981, Milner and Sauer conjectured that for any poset $\mathbb P$, if $\text{cf}(\mathbb P)$ is a singular cardinal $\lambda$, then $\mathbb P$ must contain an antichain of size $\text{cf}(\lambda)$. The conjecture is consistent and known … Continue reading

Posted in Publications
Tagged 03E04, 03E05, 03E45, 03E55, 03E65, Large Cardinals, Poset, Shelah's Strong Hypothesis, Singular Cofinality, Singular Density
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