### 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
- Genearlizations 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

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