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- A strong form of König’s lemma October 21, 2017
- 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

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

# 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