On a Theorem of N. Katz and Bases in Irreducible Representations

Part of the Developments in Mathematics book series (DEVM, volume 28)


N. Katz has shown that any irreducible representation of the Galois group of \({\mathbb{F}}_{q}((t))\) has unique extension to a special representation of the Galois group of k(t) unramified outside 0 and and tamely ramified at . In this chapter, we analyze the number of not necessarily special such extensions and relate this question to a description of bases in irreducible representations of multiplicative groups of division algebras.



The author acknowledges the support of the European Research Council during the preparation of this paper.


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© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Institute of MathematicsThe Hebrew UniversityJerusalemIsrael

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