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Related papers: W-types in Homotopy Type Theory

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The homotopical approach to intensional type theory views proofs of equality as paths. We explore what is required of an object $I$ in a topos to give such a path-based model of type theory in which paths are just functions with domain $I$.…

Logic in Computer Science · Computer Science 2023-06-22 Ian Orton , Andrew M. Pitts

Both simplicial sets and simplicial spaces are used pervasively in homotopy theory as presentations of spaces, where in both cases we extract the "underlying space" by taking geometric realization. We have a good handle on the category of…

Algebraic Topology · Mathematics 2015-10-20 Aaron Mazel-Gee

Voevodsky's univalence axiom is often motivated as a realization of the equivalence principle; the idea that equivalent mathematical structures satisfy the same properties. Indeed, in Homotopy Type Theory, properties and structures can be…

Logic in Computer Science · Computer Science 2022-11-15 Rafaël Bocquet

This paper presents a type theory in which it is possible to directly manipulate $n$-dimensional cubes (points, lines, squares, cubes, etc.) based on an interpretation of dependent type theory in a cubical set model. This enables new ways…

Logic in Computer Science · Computer Science 2016-11-14 Cyril Cohen , Thierry Coquand , Simon Huber , Anders Mörtberg

Given any model category, or more generally any category with weak equivalences, its simplicial localization is a simplicial category which can rightfully be called the "homotopy theory" of the model category. There is a model category…

Algebraic Topology · Mathematics 2007-05-23 Julia E. Bergner

Homotopy type theory is a new branch of mathematics, based on a recently discovered connection between homotopy theory and type theory, which brings new ideas into the very foundation of mathematics. On the one hand, Voevodsky's subtle and…

Logic · Mathematics 2013-08-06 The Univalent Foundations Program

When working in Homotopy Type Theory and Univalent Foundations, the traditional role of the category of sets, Set, is replaced by the category hSet of homotopy sets (h-sets); types with h-propositional identity types. Many of the properties…

Logic in Computer Science · Computer Science 2025-02-19 Daniel Gratzer , Håkon Gylterud , Anders Mörtberg , Elisabeth Stenholm

The study of homotopy theoretic phenomena in the language of type theory is sometimes loosely called `synthetic homotopy theory'. Homotopy theory in type theory is only one of the many aspects of homotopy type theory, which also includes…

Logic · Mathematics 2019-06-25 Egbert Rijke

Simplicial type theory extends homotopy type theory with a directed path type which internalizes the notion of a homomorphism within a type. This concept has significant applications both within mathematics -- where it allows for synthetic…

Logic in Computer Science · Computer Science 2026-01-16 Daniel Gratzer , Jonathan Weinberger , Ulrik Buchholtz

A multiset consists of elements, but the notion of a multiset is distinguished from that of a set by carrying information of how many times each element occurs in a given multiset. In this work we will investigate the notion of iterative…

Logic · Mathematics 2020-07-08 Håkon Robbestad Gylterud

We investigate inductive types in type theory, using the insights provided by homotopy type theory and univalent foundations of mathematics. We do so by introducing the new notion of a homotopy-initial algebra. This notion is defined by a…

Logic · Mathematics 2015-04-22 Steve Awodey , Nicola Gambino , Kristina Sojakova

Homotopy type theory is a modern foundation for mathematics that introduces the univalence axiom and is particularly suitable for the study of homotopical mathematics and its formalization via proof assistants. In order to better comprehend…

Category Theory · Mathematics 2025-08-13 Nima Rasekh

Connections between homotopy theory and type theory have recently attracted a lot of attention, with Voevodsky's univalent foundations and the interpretation of Martin-Lof's identity types in Quillen model categories as some of the…

Category Theory · Mathematics 2016-09-21 Benno van den Berg

In this note we interpret Voevodsky's Univalence Axiom in the language of (abstract) model categories. We then show that any posetal locally Cartesian closed model category $Qt$ in which the mapping $Hom^{(w)}(Z\times B,C):Qt\longrightarrow…

Category Theory · Mathematics 2011-11-16 Misha Gavrilovich , Assaf Hasson , Itay Kaplan

In this paper we construct new categorical models for the identity types of Martin-L\"of type theory, in the categories Top of topological spaces and SSet of simplicial sets. We do so building on earlier work of Awodey and Warren, which has…

Logic · Mathematics 2011-10-17 Benno van den Berg , Richard Garner

This article presents a novel approach to construct a model category structure designed to model the homotopy theory of spaces equipped with an action by the group $C_2$, where morphisms are considered to be isovariant. Our methodology…

Algebraic Topology · Mathematics 2023-12-14 Santiago Toro Oquendo

We utilise the theory of crossed simplicial groups to introduce a collection of local Quillen model structures on the category of simplicial presheaves with a compact planar Lie group action on a small Grothendieck site. As an application,…

Algebraic Topology · Mathematics 2017-06-19 Scott Balchin

It is shown that the category of presheaves of simplicial groupoids and the category of presheaves of 2-groupoids have Quillen closed model structures. Furthermore, their homotopy categories are equivalent to the homotopy categories of…

Algebraic Topology · Mathematics 2009-02-06 Zhi-Ming Luo , Peter Bubenik , Peter T. Kim

The aim of this thesis is to give a concise introduction to homotopy type theory, to Aczel's constructive set theory and to simplicial sets and their homotopy theory in particular referring to their standard model structure, showing some of…

Logic · Mathematics 2014-11-21 Cesare Gallozzi

We prove that any category of props in a symmetric monoidal model category inherits a model structure. We devote an appendix, about half the size of the paper, to the proof of the model category axioms in a general setting. We need the…

Algebraic Topology · Mathematics 2010-02-17 Benoit Fresse