ArticleOriginal scientific text
Title
Expansions of the real line by open sets: o-minimality and open cores
Authors 1, 2, 2, 3
Affiliations
- The Fields Institute, 222 College Street, Toronto, Ontario, Canada M5T 3J1
- Department of Mathematics, The Ohio State University, 231 W. 18th Avenue, Columbus, OH 43210, U.S.A.
- Department of Mathematics, University of Wisconsin, 480 Lincoln Drive, Madison, WI 53706, U.S.A.
Abstract
The open core of a structure ℜ := (ℝ,<,...) is defined to be the reduct (in the sense of definability) of ℜ generated by all of its definable open sets. If the open core of ℜ is o-minimal, then the topological closure of any definable set has finitely many connected components. We show that if every definable subset of ℝ is finite or uncountable, or if ℜ defines addition and multiplication and every definable open subset of ℝ has finitely many connected components, then the open core of ℜ is o-minimal.
Bibliography
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