Angol
I. A General Method in Proofs of Undecidability by Alfred Tarski I.1. Introduction I.2. Theories with standard formalization I.3. Undecidable and essentially undecidable theories I.4. Interpretability and weak interpretability I.5. Relativization of quantifiers I.6. Examples and applications II. Undecidability and Essential Undecidability in Arithmetic by Andrzej Mostowski, Raphael M. Robinson, and Alfred Tarski II.1. A summary of results; notation II.2. Definability in arbitrary theories II.3. Formalized arithmetic of natural numbers and its subtheories II.4. Recursiveness and definability in subtheories of arithmetic II.5. Undecidability of subtheories of arithmetic II.6. Extension of the results to other arithmetical theories and to various theories of rings III. Undecidability of the Elementary Theory of Groups by Alfred Tarski Bibliography Index
