Fragments of Arithmetic and true sentences
✍ Scribed by Andrés Cordón-Franco; Alejandro Fernández-Margarit; F. Félix Lara-Martín
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 246 KB
- Volume
- 51
- Category
- Article
- ISSN
- 0044-3050
No coin nor oath required. For personal study only.
✦ Synopsis
Paris and C. Dimitracopoulos, the class of the Πn+1-sentences true in the standard model is the only (up to deductive equivalence) consistent Πn+1-theory which extends the scheme of induction for parameter free Πn+1-formulas. Motivated by this result, we present a systematic study of extensions of bounded quantifier complexity of fragments of first-order Peano Arithmetic. Here, we improve that result and show that this property describes a general phenomenon valid for parameter free schemes. As a consequence, we obtain results on the quantifier complexity, (non)finite axiomatizability and relative strength of schemes for ∆n+1-formulas.
📜 SIMILAR VOLUMES
## Abstract We prove that every finitely generated (as a ring) model for induction for universal formulas without parameters satisfies also all true universal sentences. Mathematics Subject Classification: 03C62.
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