English
Related papers

Related papers: Modalities in homotopy type theory

200 papers

Many introductions to homotopy type theory and the univalence axiom gloss over the semantics of this new formal system in traditional set-based foundations. This expository article, written as lecture notes to accompany a 3-part mini course…

Category Theory · Mathematics 2024-03-04 Emily Riehl

The problem of defining Semi-Simplicial Types (SSTs) in Homotopy Type Theory (HoTT) has been recognized as important during the Year of Univalent Foundations at the Institute of Advanced Study. According to the interpretation of HoTT in…

Logic in Computer Science · Computer Science 2015-06-17 Fedor Part , Zhaohui Luo

Given an algebraic theory $\ct$, a homotopy $\ct$-algebra is a simplicial set where all equations from $\ct$ hold up to homotopy. All homotopy $\ct$-algebras form a homotopy variety. We give a characterization of homotopy varieties…

Category Theory · Mathematics 2007-05-23 J. Rosicky

Higher inductive types are a class of type-forming rules, introduced to provide basic (and not-so-basic) homotopy-theoretic constructions in a type-theoretic style. They have proven very fruitful for the "synthetic" development of homotopy…

Logic · Mathematics 2020-07-08 Peter LeFanu Lumsdaine , Mike Shulman

This paper discusses the development of synthetic cohomology in Homotopy Type Theory (HoTT), as well as its computer formalisation. The objectives of this paper are (1) to generalise previous work on integral cohomology in HoTT by the…

Algebraic Topology · Mathematics 2025-07-16 Axel Ljungström , Anders Mörtberg

In this paper, we study finitary 1-truncated higher inductive types (HITs) in homotopy type theory. We start by showing that all these types can be constructed from the groupoid quotient. We define an internal notion of signatures for HITs,…

Logic in Computer Science · Computer Science 2023-06-22 Niccolò Veltri , Niels van der Weide

In this paper we combine the principled approach to modalities from multimodal type theory (MTT) with the computationally well-behaved realization of identity types from cubical type theory (CTT). The result -- cubical modal type theory…

Logic in Computer Science · Computer Science 2024-12-18 Frederik Lerbjerg Aagaard , Magnus Baunsgaard Kristensen , Daniel Gratzer , Lars Birkedal

The aim of this paper is to extend the definition of motivic homotopy theory from schemes to a large class of algebraic stacks and establish a six functor formalism. The class of algebraic stacks that we consider includes many interesting…

Algebraic Geometry · Mathematics 2024-05-29 Chirantan Chowdhury

We give a model of set theory based on multisets in homotopy type theory. The equality of the model is the identity type. The underlying type of iterative sets can be formulated in Martin-L\"of type theory, without Higher Inductive Types…

Logic · Mathematics 2020-07-08 Håkon Robbestad Gylterud

This is an introduction to Homotopy Type Theory and Univalent Foundations for philosophers, written as a chapter for the book "Categories for the Working Philosopher" (ed. Elaine Landry)

Logic · Mathematics 2016-01-28 Michael Shulman

We show that categories of modules over a ring in Homotopy Type Theory (HoTT) satisfy the internal versions of the AB axioms from homological algebra. The main subtlety lies in proving AB4, which is that coproducts indexed by arbitrary sets…

Category Theory · Mathematics 2022-07-08 Jarl G. Taxerås Flaten

In this text we expose basic cases of some fundamental ideas and methods of topology. Namely, of homotopy, degree, fundamental group, covering, Whitehead invariant, etc. This is done by considering the elementary example: closed polygonal…

History and Overview · Mathematics 2026-05-07 E. Alkin , O. Nikitenko , A. Skopenkov

The goal of this dissertation is to present results from synthetic homotopy theory based on homotopy type theory (HoTT). After an introduction to Martin-L\"of's dependent type theory and homotopy type theory, key results include a synthetic…

Algebraic Topology · Mathematics 2024-09-25 Yuhang Wei

We present a development of the theory of higher groups, including infinity groups and connective spectra, in homotopy type theory. An infinity group is simply the loops in a pointed, connected type, where the group structure comes from the…

Logic in Computer Science · Computer Science 2018-02-14 Ulrik Buchholtz , Floris van Doorn , Egbert Rijke

These are notes from an informal mini-course on factorization homology, infinity-categories, and topological field theories. The target audience was imagined to be graduate students who are not homotopy theorists.

Algebraic Topology · Mathematics 2020-10-07 Araminta Amabel , Artem Kalmykov , Lukas Müller , Hiro Lee Tanaka

Mott noted a one-to-one correspondence between saturated multiplicatively closed subsets of a domain D and directed convex subgroups of the group of divisibility D. With this, we construct a functor between inclusions into saturated…

Commutative Algebra · Mathematics 2016-12-15 Jim Coykendall , Brandon Goodell

This paper introduces Relational Type Theory (RelTT), a new approach to type theory with extensionality principles, based on a relational semantics for types. The type constructs of the theory are those of System F plus relational…

Logic in Computer Science · Computer Science 2021-01-26 Aaron Stump , Benjamin Delaware , Christopher Jenkins

The first part of this dissertation defines "dependently typed algebraic theories", which are a strict subclass of the generalised algebraic theories (GATs) of Cartmell. We characterise dependently typed algebraic theories as finitary…

Category Theory · Mathematics 2021-10-07 Chaitanya Leena Subramaniam

Type theories can be formalized using the intrinsically (hard) or the extrinsically (soft) typed style. In large libraries of type theoretical features, often both styles are present, which can lead to code duplication and integration…

Logic in Computer Science · Computer Science 2021-07-19 Florian Rabe , Navid Roux

We construct an iterative method for factorising small strict n-categories into a unique (up to isomorphism) collection of small 1- categories. Following this we develop the theory to include a large class of $\infty$-categories. We use…

Category Theory · Mathematics 2014-06-11 Scott Balchin