Hostname: page-component-89b8bd64d-r6c6k Total loading time: 0 Render date: 2026-05-13T11:19:45.821Z Has data issue: false hasContentIssue false

PSEUDO-FINITE SETS, PSEUDO-O-MINIMALITY

Published online by Cambridge University Press:  26 October 2020

NADAV MEIR*
Affiliation:
DEPARTMENT OF MATHEMATICS BEN GURION UNIVERSITY OF THE NEGEV P.O.B. 653, BE’ER SHEVA 8410501, ISRAEL and INSTYTUT MATEMATYCZNY, UNIWERSYTET WROCŁAWSKI PL. GRUNWALDZKI 2/4, 50-384 WROCŁAW, POLAND E-mail: mein@math.bgu.ac.il

Abstract

We give an example of two ordered structures $\mathcal {M},\mathcal {N}$ in the same language $\mathcal {L}$ with the same universe, the same order and admitting the same one-variable definable subsets such that $\mathcal {M}$ is a model of the common theory of o-minimal $\mathcal {L}$-structures and $\mathcal {N}$ admits a definable, closed, bounded, and discrete subset and a definable injective self-mapping of that subset which is not surjective. This answers negatively two question by Schoutens; the first being whether there is an axiomatization of the common theory of o-minimal structures in a given language by conditions on one-variable definable sets alone. The second being whether definable completeness and type completeness imply the pigeonhole principle. It also partially answers a question by Fornasiero asking whether definable completeness of an expansion of a real closed field implies the pigeonhole principle.

Information

Type
Article
Copyright
© The Association for Symbolic Logic 2020

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.)

Article purchase

Temporarily unavailable