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arXiv · 0810.2810

Maps on Divisor Class Groups Induced by Ring Homomorphisms of Finite Flat Dimension

Sean Sather-Wagstaff·Sandra Spiroff
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Abstract

Let f: A\to B be a ring homomorphism between Noetherian normal integral domains. We establish a general criterion for f to induce a homomorphism Cl(f): Cl(A)\to Cl(B) on divisor class groups. For instance, this criterion applies whenever f has finite flat dimension; this special case generalizes the more classical situations where f is flat or is surjective with kernel generated by an A-regular element. We extend some of Spiroff's work on the kernels of induced maps to this more general setting.

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Sean Sather-Wagstaff, Sandra Spiroff. 2009-05-26. Maps on Divisor Class Groups Induced by Ring Homomorphisms of Finite Flat Dimension. https://arxiv.org/abs/0810.2810

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