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- A strong form of König’s lemma October 21, 2017
- 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

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

# 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