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

# 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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