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arXiv · 1912.07736

A remark on the Mayer-Vietoris double complex for singular cohomology

Roberto Frigerio·Andrea Maffei
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Abstract

Given an open cover of a paracompact topological space X, there are two natural ways to construct a map from the cohomology of the nerve of the cover to the cohomology of X. One of them is based on a partition of unity, and is more topological in nature, while the other one relies on the Mayer-Vietoris double complex, and has a more algebraic flavour. In this paper we prove that these two maps coincide, thus answering a question posed by N. V. Ivanov.

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Roberto Frigerio, Andrea Maffei. 2019-12-16. A remark on the Mayer-Vietoris double complex for singular cohomology. https://arxiv.org/abs/1912.07736

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