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Relatively projective groups as absolute Galois groups

Jochen Koenigsmann
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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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Jochen Koenigsmann. 2000-07-20. Relatively projective groups as absolute Galois groups. https://arxiv.org/abs/math/0007211

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