Categoricity of theories in , when κ* is a measurable cardinal. Part 2
We continue the work of [2] and prove that for λ successor, a λ-categorical theory T in is μ-categorical for every μ ≤ λ which is above the -beth cardinal.
Categoricity of theories in Lκω , when κ is a measurable cardinal. Part 1
We assume a theory T in the logic is categorical in a cardinal λ κ, and κ is a measurable cardinal. We prove that the class of models of T of cardinality < λ (but ≥ |T|+κ) has the amalgamation property; this is a step toward understanding the character of such classes of models.
Categoricity without equality
We study categoricity in power for reduced models of first order logic without equality.
Characterizing the powerset by a complete (Scott) sentence
This paper is part II of a study on cardinals that are characterizable by a Scott sentence, continuing previous work of the author. A cardinal κ is characterized by a Scott sentence if has a model of size κ, but no model of size κ⁺. The main question in this paper is the following: Are the characterizable cardinals closed under the powerset operation? We prove that if is characterized by a Scott sentence, then is (homogeneously) characterized by a Scott sentence, for all 0 < β₁ < ω₁....
Combinatory logic and the ω-rule
Completeness of cut-free type theories.
Computable categoricity versus relative computable categoricity
We study the notion of computable categoricity of computable structures, comparing it especially to the notion of relative computable categoricity and its relativizations. We show that every 1 decidable computably categorical structure is relatively Δ⁰₂ categorical. We study the complexity of various index sets associated with computable categoricity and relative computable categoricity. We also introduce and study a variation of relative computable categoricity, comparing it to both computable...
Consistency statements in formal theories