Definable and Non-definable Notions of Structure

  title={Definable and Non-definable Notions of Structure},
  author={Andrew W. Swan},
Definability is a key notion in the theory of Grothendieck fibrations that characterises when an external property of objects can be accessed from within the internal logic of the base of a fibration. In this paper we consider a generalisation of definability from properties of objects to structures on objects, introduced by Shulman under the name local representability. We first develop some general theory and show how to recover existing notions due to B´enabou and Johnstone as special cases. We… 



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  • S. Awodey
  • Mathematics
    Mathematical Structures in Computer Science
  • 2016
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