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arXiv · 2603.23776

A theory of twisted umkehr maps

Anssi Lahtinen
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Abstract

We develop a theory of umkehr maps for twisted generalized homology theories. In this theory, interesting umkehr maps, including generalizations of important classical ones, are induced by cartesian morphisms of a certain category opfibred over the category of spaces and continuous maps, making it possible to access them through universal properties.

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Anssi Lahtinen. 2026-03-24. A theory of twisted umkehr maps. https://arxiv.org/abs/2603.23776

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