Category theory

Pseudo-abelian category

In mathematics, specifically in category theory, a pseudo-abelian category is a category that is preadditive and is such that every idempotent has a kernel. Recall that an idempotent morphism is an endomorphism of an object with the property that . Elementary considerations show that every idempotent then has a cokernel. The pseudo-abelian condition is stronger than preadditivity, but it is weaker than the requirement that every morphism have a kernel and cokernel, as is true for abelian categories. Synonyms in the literature for pseudo-abelian include pseudoabelian and Karoubian. (Wikipedia).

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Derived Categories part 1

We give a buttload of definitions for morphisms on various categories of complexes. The derived category of an abelian category is a category whose objects are cochain complexes and whose morphisms I describe in this video.

From playlist Derived Categories

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Groups and subgroups

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From playlist Basics: Group Theory

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Kazuya Kato - Logarithmic abelian varieties

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From playlist Conférence « Géométrie arithmétique en l’honneur de Luc Illusie » - 5 mai 2021

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Every Group of Order Five or Smaller is Abelian Proof

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Every Group of Order Five or Smaller is Abelian Proof. In this video we prove that if G is a group whose order is five or smaller, then G must be abelian.

From playlist Abstract Algebra

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Local (\ell = p) Galois Deformation Rings - Ashwin Iyengar

Joint IAS/Princeton University Number Theory Seminar Topic: Local (\ell = p) Galois Deformation Rings Speaker: Ashwin Iyengar Affiliation: Johns Hopkins University Date: February 10, 2022 I will present joint work with V. Paškūnas and G. Böckle concerning deformation rings for mod p Galo

From playlist Mathematics

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GAP - 5 by Alexander Hulpke

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From playlist Group Theory and Computational Methods

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AlgTopReview4: Free abelian groups and non-commutative groups

Free abelian groups play an important role in algebraic topology. These are groups modelled on the additive group of integers Z, and their theory is analogous to the theory of vector spaces. We state the Fundamental Theorem of Finitely Generated Commutative Groups, which says that any such

From playlist Algebraic Topology

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Jean-Pierre Demailly - Kobayashi pseudo-metrics, entire curves and hyperbolicity of ... (Part 2)

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From playlist École d’été 2012 - Feuilletages, Courbes pseudoholomorphes, Applications

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Dustin Clausen - Toposes generated by compact projectives, and the example of condensed sets

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From playlist Toposes online

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Iwasawa theory of the fine Selmer groups of Galois representations by Sujatha Ramdorai

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From playlist Perfectoid Spaces 2019

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Categories 6 Monoidal categories

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From playlist Categories for the idle mathematician

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Charles Weibel: K-theory of algebraic varieties (Lecture 1)

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From playlist HIM Lectures: Trimester Program "K-Theory and Related Fields"

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Higher algebra 4: Derived categories as ∞-categories

In this video, we construct the ∞-categorical refinement of the derived category of an abelian category. This is the fourth video in our introduction to ∞-categories and Higher Algebra. Feel free to post comments and questions at our public forum at https://www.uni-muenster.de/TopologyQA

From playlist Higher Algebra

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Ariyan Javanpeykar: Arithmetic and algebraic hyperbolicity

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From playlist Algebraic and Complex Geometry

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Group theory 31: Free groups

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From playlist Group theory

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Mathematical Research Lecture -- Kyle Broder -- Curvature and Moduli

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From playlist Research Lectures

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Group theory 17: Finite abelian groups

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From playlist Group theory

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Homomorphisms in abstract algebra

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From playlist Abstract algebra

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Shane Kelly: Motives with modulus over a general base

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From playlist Representation theory's hidden motives (SMRI & Uni of Münster)

Related pages

Kernel (category theory) | Abelian category | Mathematics | Rng (algebra) | Preadditive category | Karoubi envelope | Ring (mathematics) | Category theory | Category (mathematics)