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arXiv · 2304.07729

Ng\^o support theorem and polarizability of quasi-projective commutative group schemes

Giuseppe Ancona·Dragos Fratila
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Abstract

We prove that any commutative group scheme over an arbitrary base scheme of finite type over a field with connected fibers and admitting a relatively ample line bundle is polarizable in the sense of Ng\^o. This extends the applicability of Ng\^o's support theorem to new cases, for example to Lagrangian fibrations with integral fibers and has consequences to the construction of algebraic classes.

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Giuseppe Ancona, Dragos Fratila. 2023-04-16. Ng\^o support theorem and polarizability of quasi-projective commutative group schemes. https://doi.org/10.46298/epiga.2024.12345

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