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arXiv · 2109.10037

A decomposition theorem for 0-cycles and applications

Rahul Gupta·Amalendu Krishna·Jitendra Rathore
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Abstract

We prove a decomposition theorem for the cohomological Chow group of 0-cycles on the double of a quasi-projective $R_1$-scheme over a field along a closed subscheme, in terms of the Chow groups, with and without modulus, of the scheme. This yields a significant generalization of the decomposition theorem of Binda-Krishna. As applications, we prove a moving lemma for Chow groups with modulus and an analogue of Bloch's formula for 0-cycles with modulus on singular surfaces. The latter extends a previous result of Binda-Krishna-Saito.

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Rahul Gupta, Amalendu Krishna, Jitendra Rathore. 2021-09-21. A decomposition theorem for 0-cycles and applications. https://arxiv.org/abs/2109.10037

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