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$\kappa$-categorical (Definition)

Let $ L$ be a first order language and let $ S$ be a set of $ L$-sentences. If $ \kappa$ is a cardinal, then $ S$ is said to be $ \kappa$-categorical if $ S$ has a model of cardinality $ \kappa$ and any two such models are isomorphic.

In other words, $ S$ is categorical iff it has a unique model of cardinality $ \kappa$, to within isomorphism.



"$\kappa$-categorical" is owned by Evandar.
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See Also: Vaught's test, example of a universal structure

Keywords:  model theory, logic

Attachments:
countably categorical structures (Derivation) by amador
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Cross-references: isomorphism, iff, categorical, isomorphic, cardinality, cardinal, first order language

This is version 1 of $\kappa$-categorical, born on 2002-08-29.
Object id is 3390, canonical name is KappaCategorical.
Accessed 1959 times total.

Classification:
AMS MSC03C35 (Mathematical logic and foundations :: Model theory :: Categoricity and completeness of theories)

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