Comparing Euler classes

Aravind Asok; Jean Fasel

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arXiv · 1306.5250

Comparing Euler classes

Aravind Asok·Jean Fasel

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Abstract

We establish the equality of two definitions of an Euler class in algebraic geometry: the first definition is as a "characteristic class" with values in Chow-Witt theory, while the second definition is as an "obstruction class." Along the way, we refine Morel's relative Hurewicz theorem in A^1-homotopy theory, and show how to define (twisted) Chow-Witt groups for geometric classifying spaces.

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BibTeX RIS

Aravind Asok, Jean Fasel. 2013-06-21. Comparing Euler classes. https://arxiv.org/abs/1306.5250

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