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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

### Keywords

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

# Tag Archives: tensor product graph

## 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