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arXiv · 2411.05995

On cohomology of locally profinite sets

Ko Aoki
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Abstract

We construct a locally profinite set of cardinality $\aleph_{\omega}$ with infinitely many first cohomology classes of which any distinct finite product does not vanish. Building on this, we construct the first example of a nondescendable faithfully flat map between commutative rings of cardinality $\aleph_{\omega}$ within Zermelo--Fraenkel set theory.

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BibTeXRIS

Ko Aoki. 2024-11-08. On cohomology of locally profinite sets. https://doi.org/10.1112/plms.70159

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