Title
A note on standard systems and ultrafilters
Abstract
Let (M, X) satisfies ACA(0) be such that P-X, the collection of all unbounded sets in X, admits a definable complete ultrafilter and let T be it theory extending first order arithmetic coded in C such that M thinks T is consistent. We prove that there is an end-extension N satisfies T of M such that the subsets of M coded in N are precisely those in X. As a special case we get that any Scott set with a definable ultrafilter coding it consistent theory T extending first order arithmetic is the standard system of it recursively saturated model of T.
Year
DOI
Venue
2008
10.2178/jsl/1230396749
JOURNAL OF SYMBOLIC LOGIC
DocType
Volume
Issue
Journal
73
3
ISSN
Citations 
PageRank 
0022-4812
0
0.34
References 
Authors
2
1
Name
Order
Citations
PageRank
Fredrik Engström1344.97