Pull-backs and fibrations in approximate pro-categories
نویسندگان
چکیده
منابع مشابه
Pull-backs and Fibrations in Approximate Pro-categories
In this paper we introduce the category Apro-ANR called the approximate pro-category of ANR’s, whose objects are all systems of ANR’s and whose morphisms are obtained as equivalence classes of system maps for some equivalence relation. We show that any 2-sink X f −→ Z g ←− Y in Apro-ANR admits a weak pull-back and it admits a pull-back if they are systems of compact ANR’s. Moreover, it admits a...
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ژورنال
عنوان ژورنال: Glasnik Matematicki
سال: 2008
ISSN: 0017-095X
DOI: 10.3336/gm.43.2.15