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Lusin-Sierpiński index for the internal sets

Published online by Cambridge University Press:  12 March 2014

Boško Živaljević
Boško Živaljević*
Affiliation:
Department of Mathematics, University of Sarajevo, 71000 Sarajevo, Yugoslavia
*
Department of Computer Science, Michigan State University, East Lansing, Michigan 48824, E-mail: zivaljev@cps.msu.edu
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Abstract

We prove that there exists a function f which reduces a given subset P of an internal set X of an ω1 saturated nonstandard universe to the set WF of well-founded trees possessing properties similar to those possessed by the standard part map. We use f to define the Lusin-Sierpiński index of points in X, and prove the basic properties of that index using the classical properties of the Lusin-Sierpiński index. An example of a but not set is given.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 57 , Issue 1 , March 1992 , pp. 172 - 178
Copyright
Copyright © Association for Symbolic Logic 1992

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References

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