The Borel complexity of isomorphism for theories with many types (Q998140)
From MaRDI portal
 | This is the item page for this Wikibase entity, intended for internal use and editing purposes. Please use this page instead for the normal view: The Borel complexity of isomorphism for theories with many types |
scientific article; zbMATH DE number 5178768
| Language | Label | Description | Also known as |
|---|---|---|---|
| English | The Borel complexity of isomorphism for theories with many types |
scientific article; zbMATH DE number 5178768 |
Statements
The Borel complexity of isomorphism for theories with many types (English)
0 references
10 August 2007
0 references
Within the broader question of which Borel equivalence relations can arise as the isomorphism relation on the countable models of a first-order theory, Hjorth and Kechris asked if the isomorphism relation can (as a Borel equivalence relation) be essentially countable but not tame. The author shows that the answer is no if the first-order theory has uncountably many types.
0 references
Borel equivalence relation
0 references
Scott set
0 references
S-saturated model
0 references
