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- 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

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

# Tag Archives: tensor product graph

## Hedetniemi’s conjecture for uncountable graphs

Abstract. It is proved that in Godel’s constructible universe, for every successor cardinal $\kappa$, there exist graphs $\mathcal G$ and $\mathcal H$ of size and chromatic number $\kappa$, for which the tensor product graph $\mathcal G\times\mathcal H$ is countably chromatic. … Continue reading