### Archives

### Recent blog posts

- 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

### Keywords

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