REVERSE MATHEMATICS OF FIRST-ORDER THEORIES WITH FINITELY MANY MODELS
نویسندگان
چکیده
منابع مشابه
Reverse Mathematics of First-order Theories with Finitely Many Models
We examine the reverse-mathematical strength of several theorems in classical and effective model theory concerning first-order theories and their number of models. We prove that, among these, most are equivalent to one of the familiar systems RCA0, WKL0, or ACA0. We are led to a purely model-theoretic statement that implies WKL0 but refutes ACA0 over RCA0.
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ژورنال
عنوان ژورنال: The Journal of Symbolic Logic
سال: 2014
ISSN: 0022-4812,1943-5886
DOI: 10.1017/jsl.2014.32