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- Happy new jewish year! September 24, 2014
- Square principles April 19, 2014
- Partitioning the club guessing January 22, 2014
- Walk on countable ordinals: the characteristics December 1, 2013
- Polychromatic colorings November 26, 2013
- Universal binary sequences November 14, 2013
- Syndetic colorings with applications to S and L October 26, 2013
- Open coloring and the cardinal invariant $\mathfrak b$ October 8, 2013

### Keywords

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

# 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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