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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

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

# Tag Archives: Martin’s Axiom

## Generalizations of Martin’s Axiom and the well-met condition

Recall that Martin’s Axiom asserts that for every partial order $\mathbb P$ satisfying c.c.c., and for any family $\mathcal D$ of $<2^{\aleph_0}$ many dense subsets of $\mathbb P$, there exists a directed subset $G$ of $\mathbb P$ such that $G\cap … Continue reading

## Shelah’s solution to Whitehead’s problem

Whitehead problem notes in hebrew : Table of contents Chapter 0 Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Chapter 10 Chapter 11 Chapter 12 References