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Article
Computable copies of ℓp
Computability
  • Timothy H. McNicholl, Iowa State University
Document Type
Article
Publication Version
Accepted Manuscript
Publication Date
1-1-2017
DOI
10.3233/COM-160065
Abstract

Suppose p is a computable real so that p ≥ 1. It is shown that the halting set can compute a surjective linear isometry between any two computable copies of Rᵖ. It is also shown that this result is optimal in that when p /= 2 there are two computable copies of Rᵖ with the property that any oracle that computes a linear isometry of one onto the other must also compute the halting set. Thus, Rᵖ is ∆⁰-categorical and is computably categorical if and only if p = 2. It is also demonstrated that there is a computably categorical Banach space that is not a Hilbert space. These results hold in both the real and complex case.

Comments

This is a manuscript of an article published as McNicholl, Timothy H. "Computable copies of ℓp." Computability 6, no. 4 (2017): 391-408. The final publication is available at IOS Press through http://dx.doi.org/10.3233/COM-160065. Posted with permission.

Copyright Owner
IOS Press and the authors
Language
en
File Format
application/pdf
Citation Information
Timothy H. McNicholl. "Computable copies of ℓp" Computability Vol. 6 Iss. 4 (2017) p. 391 - 408
Available at: http://works.bepress.com/timothy-mcnicholl/34/