Higher Categories and Homotopical Algebra

Higher Categories and Homotopical Algebra
Author: Denis-Charles Cisinski
Publisher: Cambridge University Press
Total Pages: 449
Release: 2019-05-02
Genre: Mathematics
ISBN: 1108473202

At last, a friendly introduction to modern homotopy theory after Joyal and Lurie, reaching advanced tools and starting from scratch.

Homotopy Theory of Higher Categories

Homotopy Theory of Higher Categories
Author: Carlos Simpson
Publisher: Cambridge University Press
Total Pages: 653
Release: 2011-10-20
Genre: Mathematics
ISBN: 1139502190

The study of higher categories is attracting growing interest for its many applications in topology, algebraic geometry, mathematical physics and category theory. In this highly readable book, Carlos Simpson develops a full set of homotopical algebra techniques and proposes a working theory of higher categories. Starting with a cohesive overview of the many different approaches currently used by researchers, the author proceeds with a detailed exposition of one of the most widely used techniques: the construction of a Cartesian Quillen model structure for higher categories. The fully iterative construction applies to enrichment over any Cartesian model category, and yields model categories for weakly associative n-categories and Segal n-categories. A corollary is the construction of higher functor categories which fit together to form the (n+1)-category of n-categories. The approach uses Tamsamani's definition based on Segal's ideas, iterated as in Pelissier's thesis using modern techniques due to Barwick, Bergner, Lurie and others.

Categorical Homotopy Theory

Categorical Homotopy Theory
Author: Emily Riehl
Publisher: Cambridge University Press
Total Pages: 371
Release: 2014-05-26
Genre: Mathematics
ISBN: 1139952633

This book develops abstract homotopy theory from the categorical perspective with a particular focus on examples. Part I discusses two competing perspectives by which one typically first encounters homotopy (co)limits: either as derived functors definable when the appropriate diagram categories admit a compatible model structure, or through particular formulae that give the right notion in certain examples. Emily Riehl unifies these seemingly rival perspectives and demonstrates that model structures on diagram categories are irrelevant. Homotopy (co)limits are explained to be a special case of weighted (co)limits, a foundational topic in enriched category theory. In Part II, Riehl further examines this topic, separating categorical arguments from homotopical ones. Part III treats the most ubiquitous axiomatic framework for homotopy theory - Quillen's model categories. Here, Riehl simplifies familiar model categorical lemmas and definitions by focusing on weak factorization systems. Part IV introduces quasi-categories and homotopy coherence.

Abstract Homotopy And Simple Homotopy Theory

Abstract Homotopy And Simple Homotopy Theory
Author: K Heiner Kamps
Publisher: World Scientific
Total Pages: 476
Release: 1997-04-11
Genre: Mathematics
ISBN: 9814502553

The abstract homotopy theory is based on the observation that analogues of much of the topological homotopy theory and simple homotopy theory exist in many other categories (e.g. spaces over a fixed base, groupoids, chain complexes, module categories). Studying categorical versions of homotopy structure, such as cylinders and path space constructions, enables not only a unified development of many examples of known homotopy theories but also reveals the inner working of the classical spatial theory. This demonstrates the logical interdependence of properties (in particular the existence of certain Kan fillers in associated cubical sets) and results (Puppe sequences, Vogt's Iemma, Dold's theorem on fibre homotopy equivalences, and homotopy coherence theory).

From Categories to Homotopy Theory

From Categories to Homotopy Theory
Author: Birgit Richter
Publisher: Cambridge University Press
Total Pages: 402
Release: 2020-04-16
Genre: Mathematics
ISBN: 1108847625

Category theory provides structure for the mathematical world and is seen everywhere in modern mathematics. With this book, the author bridges the gap between pure category theory and its numerous applications in homotopy theory, providing the necessary background information to make the subject accessible to graduate students or researchers with a background in algebraic topology and algebra. The reader is first introduced to category theory, starting with basic definitions and concepts before progressing to more advanced themes. Concrete examples and exercises illustrate the topics, ranging from colimits to constructions such as the Day convolution product. Part II covers important applications of category theory, giving a thorough introduction to simplicial objects including an account of quasi-categories and Segal sets. Diagram categories play a central role throughout the book, giving rise to models of iterated loop spaces, and feature prominently in functor homology and homology of small categories.

Towards Higher Categories

Towards Higher Categories
Author: John C. Baez
Publisher: Springer Science & Business Media
Total Pages: 292
Release: 2009-09-24
Genre: Algebra
ISBN: 1441915362

The purpose of this book is to give background for those who would like to delve into some higher category theory. It is not a primer on higher category theory itself. It begins with a paper by John Baez and Michael Shulman which explores informally, by analogy and direct connection, how cohomology and other tools of algebraic topology are seen through the eyes of n-category theory. The idea is to give some of the motivations behind this subject. There are then two survey articles, by Julie Bergner and Simona Paoli, about (infinity,1) categories and about the algebraic modelling of homotopy n-types. These are areas that are particularly well understood, and where a fully integrated theory exists. The main focus of the book is on the richness to be found in the theory of bicategories, which gives the essential starting point towards the understanding of higher categorical structures. An article by Stephen Lack gives a thorough, but informal, guide to this theory. A paper by Larry Breen on the theory of gerbes shows how such categorical structures appear in differential geometry. This book is dedicated to Max Kelly, the founder of the Australian school of category theory, and an historical paper by Ross Street describes its development.

Basic Category Theory

Basic Category Theory
Author: Tom Leinster
Publisher: Cambridge University Press
Total Pages: 193
Release: 2014-07-24
Genre: Mathematics
ISBN: 1107044243

A short introduction ideal for students learning category theory for the first time.

Motivic Homotopy Theory

Motivic Homotopy Theory
Author: Bjorn Ian Dundas
Publisher: Springer Science & Business Media
Total Pages: 228
Release: 2007-07-11
Genre: Mathematics
ISBN: 3540458972

This book is based on lectures given at a summer school on motivic homotopy theory at the Sophus Lie Centre in Nordfjordeid, Norway, in August 2002. Aimed at graduate students in algebraic topology and algebraic geometry, it contains background material from both of these fields, as well as the foundations of motivic homotopy theory. It will serve as a good introduction as well as a convenient reference for a broad group of mathematicians to this important and fascinating new subject. Vladimir Voevodsky is one of the founders of the theory and received the Fields medal for his work, and the other authors have all done important work in the subject.