The 0-th stable A^1-homotopy sheaf and quadratic zero cycles

Aravind Asok; Christian Haesemeyer

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arXiv · 1108.3854

The 0-th stable A^1-homotopy sheaf and quadratic zero cycles

Aravind Asok·Christian Haesemeyer

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Abstract

We study the 0-th stable A^1-homotopy sheaf of a smooth proper variety over a field k assumed to be infinite, perfect and to have characteristic unequal to 2. We provide an explicit description of this sheaf in terms of the theory of (twisted) Chow-Witt groups as defined by Barge-Morel and developed by Fasel. We study the notion of rational point up to stable A^1-homotopy, defined in terms of the stable A^1-homotopy sheaf of groups mentioned above. We show that, for a smooth proper k-variety X, existence of a rational point up to stable A^1-homotopy is equivalent to existence of a 0-cycle of degree 1.

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BibTeX RIS

Aravind Asok, Christian Haesemeyer. 2011-08-18. The 0-th stable A^1-homotopy sheaf and quadratic zero cycles. https://arxiv.org/abs/1108.3854

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