Witt groups and torsion Picard groups of smooth real curves

J-P. Monnier

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arXiv · math/0005244

Witt groups and torsion Picard groups of smooth real curves

J-P. Monnier

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Abstract

The Witt group of a smooth curve over a real closed field is explicitely calculated. The method uses a comparison theorem between the graded Witt group and the etale cohomology groups. In the second part of the paper, the torsion Picard group of a smooth real curve is also computed. The calculation depends on a new invariant introduced here. We prove that several problems of real algebraic geometry are related to this invariant.

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J-P. Monnier. 2000-05-24. Witt groups and torsion Picard groups of smooth real curves. https://arxiv.org/abs/math/0005244

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