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

# 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