### Archives

### Recent blog posts

- 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

### Keywords

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

# Category Archives: Notes

## 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

## Infinite Combinatorial Topology

Back in 2005, as a master student, I attended a course by Boaz Tsaban, entitled “Infinite Combinatorial Topology”. A friend and I decided to produce lecture notes, but in a somewhat loose sense, that is: we sometimes omit material given … Continue reading

Posted in Notes
Tagged b-scale, Cardinal function, Cardinal Invariants, Hereditarily Lindelöf space
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