ArticleOriginal scientific text
Title
Bimorphisms in pro-homotopy and proper homotopy
Authors 1, 2
Affiliations
- Department of Mathematics, University of Tennessee, Knoxville, TN 37996, U.S.A.
- Departamento Geometría y Topología, Facultad de Ciencias Matemáticas, Universidad Complutense, 28040 Madrid, Spain
Abstract
A morphism of a category which is simultaneously an epimorphism and a monomorphism is called a bimorphism. The category is balanced if every bimorphism is an isomorphism. In the paper properties of bimorphisms of several categories are discussed (pro-homotopy, shape, proper homotopy) and the question of those categories being balanced is raised. Our most interesting result is that a bimorphism f:X → Y of is an isomorphism if Y is movable. Recall that is the full subcategory of consisting of inverse sequences in , the homotopy category of pointed connected CW complexes.
Keywords
epimorphism, monomorphism, pro-homotopy, shape, proper homotopy
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