Universal countably chromatic graph

2025/11/10 by Kivimäki, Siiri
#03E35 #FOS: Mathematics #Logic (math.LO)

paper · doi:10.48550/arxiv.2511.07608

Abstract

We show that the existence of a universal countably chromatic graph of size ℵ₁ together with the failure of continuum hypothesis is consistent. The proof is a forcing iteration of strongly proper ccc posets. The construction works for any uncountable successor cardinal κ⁺, where κ is regular.

Citations

• Non-existence of Universal Orders in Many Cardinals

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