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- Prikry forcing may add a Souslin tree June 12, 2016
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Erdos-Hajnal graphs Slim tree projective Boolean algebra sap Kurepa Hypothesis Almost countably chromatic incompactness Jonsson cardinal Commutative cancellative semigroups tensor product graph Distributive tree Large Cardinals HOD approachability ideal Aronszajn tree Fat stationary set weak diamond Sakurai's Bell inequality Parameterized proxy principle Square-Brackets Partition Relations Diamond weak square stationary hitting Erdos Cardinal square Postprocessing function polarized partition relation Forcing Axioms Poset Hindman's Theorem Axiom R Rainbow sets Ostaszewski square Minimal Walks Microscopic Approach Constructible Universe Generalized Clubs Cardinal function Forcing b-scale Small forcing Singular cardinals combinatorics coloring number 11P99 PFA(S)[S] Chromatic number Successor of Singular Cardinal PFA Universal Sequences Chang's conjecture free Boolean algebra S-Space Non-saturation Singular Density Dushnik-Miller middle diamond Uniformly coherent reflection principles Mandelbrot set Successor of Regular Cardinal Singular coﬁnality Shelah's Strong Hypothesis stationary reflection ccc Coherent tree Cardinal Invariants Selective Ultrafilter Prikry-type forcing Foundations Fodor-type reflection Whitehead Problem Almost-disjoint famiy Rado's conjecture Souslin Tree Ascent Path Rock n' Roll Uniformization xbox Knaster 05A17 Prevalent singular cardinals P-Ideal Dichotomy 20M14 diamond star Antichain 05D10 Nonspecial tree Martin's Axiom Almost Souslin Hedetniemi's conjecture Club Guessing Fast club Absoluteness square principles Reduced Power Partition Relations Hereditarily Lindelöf space very good scale Cohen real Stevo Todorcevic Weakly compact cardinal OCA L-space

# 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