On category of co-coverings

Authors

  • Hamid Torabi Department of Pure Mathematics, Ferdowsi University of Mashhad, Mashhad, Iran.
  • Mehdi Abdullahi Department of Pure Mathematics, Ferdowsi University of Mashhad, Mashhad, Iran.
Abstract:

In this article, we introduce the concept of co-covering which is the dual of covering concept. Then, we prove several theorems being similar to the theorems that have been de-veloped for the covering concept. For example, we provide the lifting criterion for co-coverings of a topological space X, which helps us to classify them by subgroups of the group of all homeomorphisms of X.

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Journal title

volume 8  issue 2

pages  84- 90

publication date 2019-08-01

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