### 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

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