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Relatively projective groups as absolute Galois groups

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Abstract

By two well-known results, one of Ax, one of Lubotzky and van den Dries, a profinite group is projective iff it is isomorphic to the absolute Galois group of a pseudo-algebraically closed field. This paper gives an analogous characterization of relatively projective profinite groups as absolute Galois groups of regularly closed fields.

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Authors and Affiliations

  1. Fakultät für Mathematik und Informatik, Universität Konstanz, D-78434, Konstanz, Germany

    Jochen Koenigsmann

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  1. Jochen Koenigsmann
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Dedicated to Yuri Ershov on the occasion of his 60-th birthday

Heisenberg-Stipendiat der Deutschen Forschungsgemeinschaft (KO 1962/1-1).

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Koenigsmann, J. Relatively projective groups as absolute Galois groups. Isr. J. Math. 127, 93–129 (2002). https://doi.org/10.1007/BF02784528

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  • DOI: https://doi.org/10.1007/BF02784528

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