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arXiv · 2604.05554

Topology, forcing, and graph colourings

Noam Greenberg·Dominique Lecomte·Dan Turetsky·Miroslav Zelen
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Abstract

We introduce a family of forcing notions that are helpful in showing that certain graphs do not have countable colourings of (additive) Borel class alpha. We construct graphs that are ''weakly minimal'' for such colourings.

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Noam Greenberg, Dominique Lecomte, Dan Turetsky, Miroslav Zelen. 2026-04-07. Topology, forcing, and graph colourings. https://arxiv.org/abs/2604.05554

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