### 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

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

# 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
8 Comments