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

# Tag Archives: Hedetniemi’s conjecture

## 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

## Set Theory Programme on Large Cardinals and Forcing, September 2013

I gave an invited talk at the Large Cardinals and Forcing meeting, Erwin Schrödinger International Institute for Mathematical Physics, Vienna, September 23–27, 2013. Talk Title: Hedetniemi’s conjecture for uncountable graphs Abstract: It is proved that in Godel’s constructible universe, for … Continue reading

Posted in Invited Talks
Tagged Almost countably chromatic, Chromatic number, Hedetniemi's conjecture
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