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arXiv · 2603.17760

Affineness of the maximal \'{e}tale locus

Ivan Zelich
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Abstract

In this paper we will prove a strong version of the celebrated purity of the ramification locus theorem in algebraic geometry. Our key input is a Tor-independence result for global sections of \'{e}tale schemes over excellent regular local rings, which we will prove by tilting to perfect rings.

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Ivan Zelich. 2026-03-18. Affineness of the maximal \'{e}tale locus. https://arxiv.org/abs/2603.17760

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