An extended predicative definition of the Mahlo universe

نویسندگان

  • Reinhard Kahle
  • Anton Setzer
چکیده

In this article we develop a Mahlo universe in Explicit Mathematics using extended predicative methods. Our approach differs from the usual construction in type theory, where the Mahlo universe has a constructor that refers to all total functions from families of sets in the Mahlo universe into itself; such a construction is, in the absence of a further analysis, impredicative. By extended predicative methods we mean that universes are constructed from below, even if they have impredicative characteristics.

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تاریخ انتشار 2010