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Reduction theory for a rational function field

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Abstract

LetG be a split reductive group over a finite field Fq. LetF = Fq(t) and let A denote the adèles ofF. We show that every double coset inG(F)/G(A)/K has a representative in a maximal split torus ofG. HereK is the set of integral adèlic points ofG. WhenG ranges over general linear groups this is equivalent to the assertion that any algebraic vector bundle over the projective line is isomorphic to a direct sum of line bundles.

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  1. Max-Planck-Institut für Mathematik, Postfach 7280, D-53072, Bonn, Germany

    Amritanshu Prasad

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  1. Amritanshu Prasad
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Prasad, A. Reduction theory for a rational function field. Proc. Indian Acad. Sci. (Math. Sci.) 113, 153–163 (2003). https://doi.org/10.1007/BF02829764

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  • DOI: https://doi.org/10.1007/BF02829764

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