Concrete categories and injectivity

  • H. Bargenda
  • H. Herrlich
  • G. E. Strecker
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 239)


The paper consists of two parts. In the first part the concepts of injective objects, essential extensions, and injective hulls are illustrated by examples of known characterizations of these concepts in various familiar settings. In the second part the above notions are considered in quasicategories whose objects are concrete categories. It turns out that several types of ‘completions’ of concrete categories can be characterized as injective hulls.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • H. Bargenda
    • 1
  • H. Herrlich
    • 1
  • G. E. Strecker
    • 2
  1. 1.F.B. MathematikUniversitat BremenBremenFed. Rep. Germany
  2. 2.Dept. of MathematicsKansas State UniversityManhattanU.S.A.

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