Terpene October 14, 2016October 24, 2016 thcscience_admin In category theory, a tetracategory is a weakened definition of a 4-category. See also[edit] Weak n-category infinity category External links[edit] Notes on tetracategories by Todd Trimble. Category theoryKey conceptsKey concepts Category Abelian Additive Concrete Pre-abelian Preadditive Bicategory Adjoint functors CCC Commutative diagram End Exponential Functor Kan extension Morphism Natural transformation Universal property Universal constructionsLimits Terminal objects Products Equalizers Kernels Pullbacks Inverse limit Colimits Initial objects Coproducts Coequalizers Cokernels and quotients Pushout Direct limit Algebraic categories Sets Relations Magmas Groups Abelian groups Rings (Fields) Modules (Vector spaces) Constructions on categories Free category Functor category Kleisli category Opposite category Quotient category Product category Comma category Subcategory Higher category theory Key concepts Categorification Enriched category Higher-dimensional algebra Homotopy hypothesis Model category Simplex category String diagram Topos n-categoriesWeak n-categories Bicategory (pseudofunctor) Tricategory Tetracategory Kan complex ∞-groupoid ∞-topos Strict n-categories 2-category (2-functor) 3-category Categorified concepts 2-group 2-ring En-ring (Traced)(Symmetric) monoidal category n-group n-monoid Category Outline Glossary