Table of Contents
Fetching ...

Logical Structure on Inverse Functor Categories

Marcelo Fiore, Chris Kapulkin, Yufeng Li

Abstract

Inspired by recent work on the categorical semantics of dependent type theories, we investigate the following question: When is logical structure (crucially, dependent-product and subobject-classifier structure) induced from a category to categories of diagrams in it? Our work offers several answers, providing a variety of conditions on both the category itself and the indexing category of diagrams. Additionally, motivated by homotopical considerations, we investigate the case when the indexing category is equipped with a class of weak equivalences and study conditions under which the localization map induces a structure-preserving functor between presheaf categories.

Logical Structure on Inverse Functor Categories

Abstract

Inspired by recent work on the categorical semantics of dependent type theories, we investigate the following question: When is logical structure (crucially, dependent-product and subobject-classifier structure) induced from a category to categories of diagrams in it? Our work offers several answers, providing a variety of conditions on both the category itself and the indexing category of diagrams. Additionally, motivated by homotopical considerations, we investigate the case when the indexing category is equipped with a class of weak equivalences and study conditions under which the localization map induces a structure-preserving functor between presheaf categories.

Paper Structure

This paper contains 14 sections, 39 theorems, 35 equations.

Key Result

lemma 1.1

If $\mathbb{G}$ is connected or $\mathcal{E}$ admits an initial object then a map in $\mathcal{E}^\mathbb{G}$ is a mono exactly when each of its components are.

Theorems & Definitions (49)

  • lemma 1.1
  • proposition 1.2
  • definition 1.3
  • lemma 1.5
  • lemma 1.6
  • lemma 1.7
  • theorem 1.8: cf. kl21
  • definition 2.1
  • example 2.2: mm94
  • lemma 2.5
  • ...and 39 more