### 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

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