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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

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

# Tag Archives: 05C76

## 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