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Homotopy Type Theory: Univalent Foundations of Mathematics N54F33XE07

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e1: edition

Contents
  • chapter 1: Homotopy type theory
  • section 1.1: Types are higher groupoids
  • section 1.2: Functions are functors
  • section 1.3: Type families are fibrations
  • section 1.4: Homotopies and equivalences
  • section 1.5: The higher groupoid structure of type formers
  • section 1.6: Cartesian product types
  • section 1.7: \texorpdfstring{$\Sigma$}{Σ}-types
  • section 1.8: The unit type
  • section 1.9: \texorpdfstring{$\Pi$}{Π}-types and the function extensionality axiom
  • section 1.10: Universes and the univalence axiom
  • section 1.11: Identity type
  • section 1.12: Coproducts
  • section 1.13: Natural numbers
  • section 1.14: Example: equality of structures
  • subsection 1.14.1: Lifting equivalences
  • subsection 1.14.2: Equality of semigroups
  • section 1.15: Universal properties
  • chapter 2: Category theory
  • section 2.1: Categories and precategories
  • section 2.2: Functors and transformations
  • section 2.3: Adjunctions
  • section 2.4: Equivalences
  • section 2.5: The Yoneda lemma
  • section 2.6: Strict categories
  • section 2.7: \texorpdfstring{$\dagger$}{†}-categories
  • section 2.8: The structure identity principle
  • section 2.9: The Rezk completion
  • chapter 3: Equivalences
  • section 3.1: Quasi-inverses
  • section 3.2: Half adjoint equivalences
  • section 3.3: Bi-invertible maps
  • section 3.4: Contractible fibers
  • section 3.5: On the definition of equivalences
  • section 3.6: Surjections and embeddings
  • section 3.7: Closure properties of equivalences
  • section 3.8: The object classifier
  • section 3.9: Univalence implies function extensionality
  • chapter 4: Formal type theory
  • section: Preliminaries
  • section 4.1: The first presentation
  • subsection 4.1.1: Type universes
  • subsection 4.1.2: Dependent function types (\texorpdfstring{$\Pi$}{Π}-types)
  • subsection 4.1.3: Dependent pair types (\texorpdfstring{$\Sigma$}{Σ}-types)
  • subsection 4.1.4: Coproduct types
  • subsection 4.1.5: The finite types
  • subsection 4.1.6: Natural numbers
  • subsection 4.1.7: \texorpdfstring{$W$}{W}-types
  • subsection 4.1.8: Identity types
  • section 4.2: The second presentation
  • subsection 4.2.1: Contexts
  • subsection 4.2.2: Structural rules
  • subsection 4.2.3: Type universes
  • subsection 4.2.4: Dependent function types (\texorpdfstring{$\Pi$}{Π}-types)
  • subsection 4.2.5: Dependent pair types (\texorpdfstring{$\Sigma$}{Σ}-types)
  • subsection 4.2.6: Coproduct types
  • subsection 4.2.7: The empty type \texorpdfstring{$\emptyt$}{0}
  • subsection 4.2.8: The unit type \texorpdfstring{$\unit$}{1}
  • subsection 4.2.9: The natural number type
  • subsection 4.2.10: Identity types
  • subsection 4.2.11: Definitions
  • section 4.3: Homotopy type theory
  • subsection 4.3.1: Function extensionality and univalence
  • subsection 4.3.2: The circle
  • section 4.4: Basic metatheory
  • chapter 5: Higher inductive types
  • section 5.1: Introduction
  • section 5.2: Induction principles and dependent paths
  • section 5.3: The interval
  • section 5.4: Circles and spheres
  • section 5.5: Suspensions
  • section 5.6: Cell complexes
  • section 5.7: Hubs and spokes
  • section 5.8: Pushouts
  • section 5.9: Truncations
  • section 5.10: Quotients
  • section 5.11: Algebra
  • section 5.12: The flattening lemma
  • section 5.13: The general syntax of higher inductive definitions
  • chapter 6: Homotopy \texorpdfstring{$n$}{n}-types
  • section 6.1: Definition of \texorpdfstring{$n$}{n}-types
  • section 6.2: Uniqueness of identity proofs and Hedberg's theorem
  • section 6.3: Truncations
  • section 6.4: Colimits of \texorpdfstring{$n$}{n}-types
  • section 6.5: Connectedness
  • section 6.6: Orthogonal factorization
  • section 6.7: Modalities
  • chapter 7: Homotopy theory
  • section 7.1: \texorpdfstring{$\pi_1(S^1)$}{π₁(S¹)}
  • subsection 7.1.1: Getting started
  • subsection 7.1.2: The classical proof
  • subsection 7.1.3: The universal cover in type theory
  • subsection 7.1.4: The encode-decode proof
  • subsection 7.1.5: The homotopy-theoretic proof
  • subsection 7.1.6: The universal cover as an identity system
  • section 7.2: Connectedness of suspensions
  • section 7.3: \texorpdfstring{$\pi_{k \le n}$}{π\_(k≤n)} of an \texorpdfstring{$n$}{n}-connected space and \texorpdfstring{$\pi_{k < n}(\Sn ^n)$}{π\_(k<n)(Sⁿ)}
  • section 7.4: Fiber sequences and the long exact sequence
  • section 7.5: The Hopf fibration
  • subsection 7.5.1: Fibrations over pushouts
  • subsection 7.5.2: The Hopf construction
  • subsection 7.5.3: The Hopf fibration
  • section 7.6: The Freudenthal suspension theorem
  • section 7.7: The van Kampen theorem
  • subsection 7.7.1: Naive van Kampen
  • subsection 7.7.2: The van Kampen theorem with a set of basepoints
  • section 7.8: Whitehead's theorem and Whitehead's principle
  • section 7.9: A general statement of the encode-decode method
  • section 7.10: Additional Results
  • chapter 8: Induction
  • section 8.1: Introduction to inductive types
  • section 8.2: Uniqueness of inductive types
  • section 8.3: \texorpdfstring{$\w$}{W}-types
  • section 8.4: Inductive types are initial algebras
  • section 8.5: Homotopy-inductive types
  • section 8.6: The general syntax of inductive definitions
  • section 8.7: Generalizations of inductive types
  • section 8.8: Identity types and identity systems
  • chapter: Introduction
  • subsection: Type theory
  • subsection: Homotopy type theory
  • subsection: Univalent foundations
  • subsection: Higher inductive types
  • subsection: Sets in univalent foundations
  • subsection: Informal type theory
  • subsection: Constructivity
  • subsection: Open problems
  • subsection: How to read this book
  • chapter 9: Sets and logic
  • section 9.1: Sets and \texorpdfstring{$n$}{n}-types
  • section 9.2: Propositions as types?
  • section 9.3: Mere propositions
  • section 9.4: Classical vs.\ intuitionistic logic
  • section 9.5: Subsets and propositional resizing
  • section 9.6: The logic of mere propositions
  • section 9.7: Propositional truncation
  • section 9.8: The axiom of choice
  • section 9.9: The principle of unique choice
  • section 9.10: When are propositions truncated?
  • section 9.11: Contractibility
  • section: Notes
  • section: Exercises
  • part I: Foundations
  • part II: Mathematics
  • part: Appendix
  • chapter: Preface
  • subsection: IAS Special Year on Univalent Foundations
  • subsection: About this book
  • appendix A: Type theory
  • section A.1: Type theory versus set theory
  • section A.2: Function types
  • section A.3: Universes and families
  • section A.4: Dependent function types (\texorpdfstring{$\Pi$}{Π}-types)
  • section A.5: Product types
  • section A.6: Dependent pair types (\texorpdfstring{$\Sigma$}{Σ}-types)
  • section A.7: Coproduct types
  • section A.8: The type of booleans
  • section A.9: The natural numbers
  • section A.10: Pattern matching and recursion
  • section A.11: Propositions as types
  • section A.12: Identity types
  • subsection A.12.1: Path induction
  • subsection A.12.2: Equivalence of path induction and based path induction
  • subsection A.12.3: Disequality
  • appendix B: Real numbers
  • section B.1: The field of rational numbers
  • section B.2: Dedekind reals
  • subsection B.2.1: The algebraic structure of Dedekind reals
  • subsection B.2.2: Dedekind reals are Cauchy complete
  • subsection B.2.3: Dedekind reals are Dedekind complete
  • section B.3: Cauchy reals
  • subsection B.3.1: Construction of Cauchy reals
  • subsection B.3.2: Induction and recursion on Cauchy reals
  • subsection B.3.3: The algebraic structure of Cauchy reals
  • subsection B.3.4: Cauchy reals are Cauchy complete
  • section B.4: Comparison of Cauchy and Dedekind reals
  • section B.5: Compactness of the interval
  • section B.6: The surreal numbers
  • appendix C: Set theory
  • section C.1: The category of sets
  • subsection C.1.1: Limits and colimits
  • subsection C.1.2: Images
  • subsection C.1.3: Quotients
  • subsection C.1.4: \texorpdfstring{$\uset$}{Set} is a \texorpdfstring{$\Pi\mathsf{W}$}{ΠW}-pretopos
  • subsection C.1.5: The axiom of choice implies excluded middle
  • section C.2: Cardinal numbers
  • section C.3: Ordinal numbers
  • section C.4: Classical well-orderings
  • section C.5: The cumulative hierarchy
  • chapter: Index of symbols

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