### 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

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

# Tag Archives: Mandelbrot set

## A natural Mandelbrot set

Chris Hadfield is a Canadian astronaut, with a very high-profile twitter account. He posts there beautiful photos everyday, and I (plus half a million followers) enjoy it very much. Today, Chris posted the following picture: and I find it quite … Continue reading