## Journal of Symbolic Logic

### Isomorphism relations on computable structures

#### Abstract

We study the complexity of the isomorphism relation on classes of computable structures. We use the notion of FF-reducibility introduced in [9] to show completeness of the isomorphism relation on many familiar classes in the context of all Σ¹₁ equivalence relations on hyperarithmetical subsets of ω.

#### Article information

Source
J. Symbolic Logic Volume 77, Issue 1 (2012), 122-132.

Dates
First available in Project Euclid: 20 January 2012

Permanent link to this document
http://projecteuclid.org/euclid.jsl/1327068695

Digital Object Identifier
doi:10.2178/jsl/1327068695

Mathematical Reviews number (MathSciNet)
MR2951633

Zentralblatt MATH identifier
06025962

#### Citation

Fokina, Ekaterina B.; Friedman, Sy-David; Harizanov, Valentina; Knight, Julia F.; McCoy, Charles; Montalbán, Antonio. Isomorphism relations on computable structures. J. Symbolic Logic 77 (2012), no. 1, 122--132. doi:10.2178/jsl/1327068695. http://projecteuclid.org/euclid.jsl/1327068695.

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