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The twisted forms of a semisimple group over an \(\mathbb{F}_q\)-curve. (English. French summary) Zbl 1507.11057

Summary: Let \(C\) be a smooth, projective and geometrically connected curve defined over a finite field \(\mathbb{F}_q\). Given a semisimple \(C-S\)-group scheme \(\underline{G}\) where \(S\) is a finite set of closed points of \(C\), we describe the set of \(( \mathcal{O}_S\)-classes of) twisted forms of \(\underline{G}\) in terms of geometric invariants of its fundamental group \(F(\underline{G})\).

MSC:

11G20 Curves over finite and local fields
11G45 Geometric class field theory
11R29 Class numbers, class groups, discriminants

References:

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