منابع مشابه
Categoricity and Infinitary Logics
We point out a gap in Shelah’s proof of the following result: Claim 0.1. Let K be an abstract elementary class categorical in unboundedly many cardinals. Then there exists a cardinal λ such that whenever M,N ∈ K have size at least λ, M ≤ N if and only if M L∞,LS(K)+ N . The importance of the claim lies in the following theorem, implicit in Shelah’s work: Theorem 0.2. Assume the claim. Let K be ...
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We provide a strongly complete infinitary proof system for hybrid logic. This proof system can be extended with countably many sequents. Thus, although these logics may be non-compact, strong completeness proofs are provided for infinitary hybrid versions of non-compact logics like ancestral logic and Segerberg’s modal logic with the bounded chain condition. This extends the completeness result...
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We give a general technique on how to produce counterexamples to Beth’s definability (and weak definability) theorem. The method is then applied for various infinitary, cardinality quantifier logics and ∆-closure of such logics. I would like to thank Alice Leonhardt for the beautiful typing. AMS-Classification: 03C95, 03C20, 03E55, 03C55, 03C30. The author would like to thank the United States ...
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ژورنال
عنوان ژورنال: Information and Computation
سال: 1992
ISSN: 0890-5401
DOI: 10.1016/0890-5401(92)90021-7