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Simple and hyperhypersimple vector spaces1

Published online by Cambridge University Press:  12 March 2014

Allen Retzlaff*
Affiliation:
Cornell University, Ithaca, NY 14853 State University of New York, Purchase, NY 10577

Abstract

Let V be a fixed, fully effective, infinite dimensional vector space. Let be the lattice consisting of the recursively enumerable (r.e.) subspaces of V, under the operations of intersection and weak sum (see §1 for precise definitions). In this article we examine the algebraic properties of .

Early research on recursively enumerable algebraic structures was done by Rabin [14], Frölich and Shepherdson [5], Dekker [3], Hamilton [7], and Guhl [6]. Our results are based upon the more recent work concerning vector spaces of Metakides and Nerode [12], Crossley and Nerode [2], Remmel [15], [16], and Kalantari [8].

In the main theorem below, we extend a result of Lachlan from the lattice of r.e. sets to . We define hyperhypersimple vector spaces, discuss some of their properties and show if A, B, and A is a hyperhypersimple subspace of B then there is a recursive space C such that A + C = B. It will be proven that if V and the lattice of superspaces of V is a complemented modular lattice then V is hyperhypersimple. The final section contains a summary of related results concerning maximality and simplicity.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1978

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Footnotes

1

This research was partially supported by NSF grant number MPS 74-06378.

References

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