Abstract:
This paper is a survey of some topics in computable structure theory, illustrating the power of certain infinitary sentences to describe mathematical structures and classes of structures. It includes classical results such as the Scott isomorphism theorem and the Lopez-Escobar theorem, and work of Friedman and Stanley on comparing classes of structures according to the complexity of their invariants. It also includes more recent results, in particular, on torsion-free Abelian groups.
Fulltext:
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