Invariance results for definable extensions of groups
نویسندگان
چکیده
We show that in an o-minimal expansion of an ordered group finite definable extensions of a definable group which is defined in a reduct are already defined in the reduct. A similar result is proved for finite topological extensions of definable groups defined in o-minimal expansions of the ordered set of real numbers. ∗With partial support from the FCT (Fundação para a Ciência e Tecnologia) program POCI 2010 (Portugal/FEDER-EU) and FCT (Fundação para a Ciência e Tecnologia) project PTDC/MAT/101740/2008. †Supported by NSERC while a post-doc at McMaster University, Canada. MSC: 03C64; 20E99.
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عنوان ژورنال:
- Arch. Math. Log.
دوره 50 شماره
صفحات -
تاریخ انتشار 2011