### 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

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