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arXiv · 0908.0096

A local-global principle for weak approximation on varieties over function fields

Mike Roth·Jason Michael Starr
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Abstract

We present a new perspective on the weak approximation conjecture of Hassett and Tschinkel: formal sections of a rationally connected fibration over a curve can be approximated to arbitrary order by regular sections. The new approach involves the study of how ideal sheaves pullback to Cartier divisors.

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Mike Roth, Jason Michael Starr. 2009-09-04. A local-global principle for weak approximation on varieties over function fields. https://arxiv.org/abs/0908.0096

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