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An intuitionistic set-theoretical model of fully dependent CC$^{\boldsymbol\omega}$

Published online by Cambridge University Press:  17 April 2023

Masahiro Sato
Affiliation:
SIOS Technology, Inc., 2-12-3 Minami-Asabu, Minato-ku, Tokyo 106-0047, Japan
Jacques Garrigue*
Affiliation:
Graduate School of Mathematics, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
*
*Corresponding author. Email: garrigue@math.nagoya-u.ac.jp

Abstract

Werner’s set-theoretical model is one of the simplest models of CIC. It combines a functional view of predicative universes with a collapsed view of the impredicative sort “ ${\tt Prop}$ ”. However, this model of ${\tt Prop}$ is so coarse that the principle of excluded middle $P \lor \neg P$ holds. Following our previous work, we interpret ${\tt Prop}$ into a topological space (a special case of Heyting algebra) to make the model more intuitionistic without sacrificing simplicity. We improve on that work by providing a full interpretation of dependent product types, using Alexandroff spaces. We also extend our approach to inductive types by adding support for ${\mathsf{list}}$ s.

Type
Paper
Copyright
© The Author(s), 2023. Published by Cambridge University Press

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