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

# 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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