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Effective cardinals in the nonstandard universe

Vladimir Kanovei·Michael Reeken
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Abstract

We study the structure of effective cardinals in the nonstandard set universe of Hrbacek set theory HST. Some results resemble those known in descriptive set theory in the domain of Borel reducibility of equivalence relations.

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Vladimir Kanovei, Michael Reeken. 2005-12-02. Effective cardinals in the nonstandard universe. https://doi.org/10.1142/6255

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