Skip to content

Opening book details…

Can I read Stability of Recursive Structures in Arithmetical Degrees on EtoBox?

Stability of Recursive Structures in Arithmetical Degrees by C.J. Ash is a Computer Science article available to read on EtoBox.

What is Stability of Recursive Structures in Arithmetical Degrees about?

We say that a recursive structure 92 is A°-stable if, for every recursive structure ~, every isomorphism f: 92--~ is A ° in Kleene's arithmetical hierarchy.Goncharov in has obtained a necessary and sufficient recursive-syntactic condition for a structure 92 to be recursively stable [i.e. A°-stable], under the assumption that the existential diagram of 92 is recursive. This result is also obtained as a corollary in Ash & Nerode . In both cases, the proof uses a finite injury priority argument.We generalize this result by establishing, subject to further assumptions of recursiveness in 92, analogous conditions for 92 to be A°-stable, which we summarize as "92 has a formally A ° enumeration".For A°-stability the proof uses an infinite injury argument and for/t°-stability a 'monstrous' injury argument. We show how this process can be continued for all n. 114 C.J. Ash[The direct construction of recursive copies of (to n, < ) with highly nonrecursive properties is discussed in . The recursive stability of structures such as (o~, +, < ) and (~, +, -, < ) is considered in .]The notion of zl°-stability is to be carefully distinguished from that of zl°-categoricity. We define a recursive str

Who reads Stability of Recursive Structures in Arithmetical Degrees?

It is typically read by researchers, students, and practitioners in Computer Science.

Author
C.J. Ash
Published
1986
Language
EN
Field
Computer Science (Physical Sciences)

More by C.J. Ash

Browse all works by C.J. Ash