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