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The algebraic nature of the elementary theory of PRC fields. (English) Zbl 0675.12016

A field K is PAC (resp. PRC) if every nonempty absolutely irreducible variety V defined over K has a K-rational point (resp. if each such V has a K-rational point provided it has a simple \(\bar K\)-rational point for every real closure \(\bar K\) of K). - After M. Fried and M. Jarden [“Field arithmetic”, Ergebn. Math. Grenzgebiete, 3. Folge 11 (1986; Zbl 0625.12001)], the elementary theory of algebraic PAC fields determines the elementary theory of all PAC fields (thus a sentence \(\theta\) is true in each field of characteristic 0 if it is true in each PAC field which is algebraic over \({\mathbb{Q}}).\)
The scope of this paper is to prove an analogous result for PRC and maximal PRC fields. Also is proved that the absolute Galois group of a maximal PRC field is a free product of groups of order 2 in the category of pro-2 groups and conversely, each such group is isomorphic to the absolute Galois group of a maximal PRC field.
Reviewer: D.Busneag

MSC:

12L12 Model theory of fields
14G05 Rational points
12L10 Ultraproducts and field theory

Citations:

Zbl 0625.12001

References:

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