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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
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- Partitioning the club guessing January 22, 2014

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

# 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