Title
Decidable Algebraic Fields.
Abstract
We discuss the connection between decidability of a theory of a large algebraic extensions of Q and the recursiveness of the field as a subset of a fixed algebraic closure. In particular, we prove that if an algebraic extension K of Q has a decidable existential theory, then within any fixed algebraic closure (Q) over tilde of Q, the field K must be conjugate over Q to a field which is recursive as a subset of the algebraic closure. We also show that for each positive integer e there are infinitely many e-tuples sigma is an element of Gal(Q)(e) such that the field (Q) over tilde(sigma) is primitive recursive in (Q) over tilde and its elementary theory is primitive recursively decidable. Moreover, (Q) over tilde(sigma) is PAC and Gal((Q) over tilde(sigma)) is isomorphic to the free profinite group on e generators.
Year
DOI
Venue
2017
10.1017/jsl.2017.10
JOURNAL OF SYMBOLIC LOGIC
Keywords
DocType
Volume
decidable theory,recursive subsets
Journal
82
Issue
ISSN
Citations 
2
0022-4812
0
PageRank 
References 
Authors
0.34
0
2
Name
Order
Citations
PageRank
Moshe Jarden111.73
Alexandra Shlapentokh2128.14