Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-25T06:38:02.761Z Has data issue: false hasContentIssue false

Isomorphisms between HEO and HROE, ECF and ICFE

Published online by Cambridge University Press:  12 March 2014

Marc Bezem*
Affiliation:
Korenbloemstraat 44, 3551 Gn Utrecht, The, Netherlands

Abstract

In this paper it will be shown that HEO and HROE are isomorphic with respect to extensional equality. This answers a question of Troelstra [T, 2.4.12, p. 128]. The main problem is to extend effective operations to a larger domain. This will be achieved by a modification of the proof of the continuity of effective operations. Following a suggestion of A. S. Troelstra, similar results were obtained for ECF(U) and ICFE(U), where U is any universe of functions closed under “recursive in”.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1985

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[H] Heyting, A. (editor), Constructivity in mathematics, North-Holland, Amsterdam, 1959.Google Scholar
[Kl] Kleene, S. C., Countable functionals, [H, pp. 81100].Google Scholar
[Kr] Kreisel, G., Interpretation of analysis by means of constructive functionals of finite type, [H, pp. 101–128].Google Scholar
[KLS] Kreisel, G., Lacombe, D. and Shoenfield, J. R., Partial recursive functionals and effective operations, [H, pp. 290–297].Google Scholar
[T] Troelstra, A. S., Metamathematical investigation of intuitionistic arithmetic and analysis, Lecture Notes in Mathematics, vol. 344, Springer-Verlag, Berlin, 1973.CrossRefGoogle Scholar
[Z] Zucker, J. I., Proof-theoretic studies of iterated inductive definitions and subsystems of analysis, Ph.D. Thesis, Stanford University, Stanford, California, 1971.Google Scholar