Abelian group theory

Rank of an abelian group

In mathematics, the rank, Prüfer rank, or torsion-free rank of an abelian group A is the cardinality of a maximal linearly independent subset. The rank of A determines the size of the largest free abelian group contained in A. If A is torsion-free then it embeds into a vector space over the rational numbers of dimension rank A. For finitely generated abelian groups, rank is a strong invariant and every such group is determined up to isomorphism by its rank and torsion subgroup. Torsion-free abelian groups of rank 1 have been completely classified. However, the theory of abelian groups of higher rank is more involved. The term rank has a different meaning in the context of elementary abelian groups. (Wikipedia).

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Group theory 17: Finite abelian groups

This lecture is part of a mathematics course on group theory. It shows that every finitely generated abelian group is a sum of cyclic groups. Correction: At 9:22 the generators should be g, h+ng not g, g+nh

From playlist Group theory

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Group theory 31: Free groups

This lecture is part of an online math course on group theory. We review free abelian groups, then construct free (non-abelian) groups, and show that they are given by the set of reduced words, and as a bonus find that they are residually finite.

From playlist Group theory

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Groups and subgroups

Jacob explains the fundamental concepts in group theory of what groups and subgroups are, and highlights a few examples of groups you may already know. Abelian groups are named in honor of Niels Henrik Abel (https://en.wikipedia.org/wiki/Niels_Henrik_Abel), who pioneered the subject of

From playlist Basics: Group Theory

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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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Normal subgroups

Before we carry on with our coset journey, we need to discover when the left- and right cosets are equal to each other. The obvious situation is when our group is Abelian. The other situation is when the subgroup is a normal subgroup. In this video I show you what a normal subgroup is a

From playlist Abstract algebra

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Visual Group Theory, Lecture 4.4: Finitely generated abelian groups

Visual Group Theory, Lecture 4.4: Finitely generated abelian groups We begin this lecture by proving that the cyclic group of order n*m is isomorphic to the direct product of cyclic groups of order n and m if and only if gcd(n,m)=1. Then, we classify all finite abelian groups by decomposi

From playlist Visual Group Theory

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Group theory 18: Nilpotent groups

This lecture is part of an online mathematics course on group theory. It lists the groups of order 16, and shows that a finite group is nilpotent if and only if it is a product of p-groups.

From playlist Group theory

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Every Subgroup of an Abelian Group is Normal Proof

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Every Subgroup of an Abelian Group is Normal Proof

From playlist Abstract Algebra

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Abstract Algebra - 11.1 Fundamental Theorem of Finite Abelian Groups

We complete our study of Abstract Algebra in the topic of groups by studying the Fundamental Theorem of Finite Abelian Groups. This tells us that every finite abelian group is a direct product of cyclic groups of prime-power order. Video Chapters: Intro 0:00 Before the Fundamental Theorem

From playlist Abstract Algebra - Entire Course

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Rachel Pries - The geometry of p-torsion stratifications of the moduli space of curve

The geometry of p-torsion stratifications of the moduli space of curve

From playlist 28ème Journées Arithmétiques 2013

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Christelle Vincent, Exploring angle rank using the LMFDB

VaNTAGe Seminar, February 15, 2022 License: CC-NC-BY-SA Links to some of the papers mentioned in the talk: Dupuy, Kedlaya, Roe, Vincent: https://arxiv.org/abs/2003.05380 Dupuy, Kedlaya, Zureick-Brown: https://arxiv.org/abs/2112.02455 Zarhin 1979: https://link.springer.com/article/10.100

From playlist Curves and abelian varieties over finite fields

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Taylor Dupuy (Nov. 13, 2020): Abelian Varieties Over Finite Fields in the LMFDB

I will talk about things around the LMFDB database of isogeny classes of abelian varieties over finite fields (and maybe even about isomorphism classes). These could include: --"Sato-Ain't" distributions, --weird Tate classes, --Bizzaro Hodge co-levels (and very strange Ax-Katz/Cheval

From playlist Seminar Talks

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Homotopy of Character Varieties by Sean Lawton

Higgs bundles URL: http://www.icts.res.in/program/hb2016 DATES: Monday 21 Mar, 2016 - Friday 01 Apr, 2016 VENUE : Madhava Lecture Hall, ICTS Bangalore DESCRIPTION: Higgs bundles arise as solutions to noncompact analog of the Yang-Mills equation. Hitchin showed that irreducible solutio

From playlist Higgs Bundles

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Karen Vogtmann - On the cohomological dimension of automorphism groups of RAAGs

The class of right-angled Artin groups (RAAGs) includes free groups and free abelian groups, Both of these have extremely interesting automorphism groups, which share some properties and not others. We are interested in automorphism groups of general RAAGs, and in particular

From playlist Groupes, géométrie et analyse : conférence en l'honneur des 60 ans d'Alain Valette

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The Geometric Langlands conjecture and non-abelian Hodge theory (Lecture 3) by Ron Donagi

Program: Quantum Fields, Geometry and Representation Theory ORGANIZERS : Aswin Balasubramanian, Saurav Bhaumik, Indranil Biswas, Abhijit Gadde, Rajesh Gopakumar and Mahan Mj DATE & TIME : 16 July 2018 to 27 July 2018 VENUE : Madhava Lecture Hall, ICTS, Bangalore The power of symmetries

From playlist Quantum Fields, Geometry and Representation Theory

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Taylor Dupuy 5/9/14 Part 1

Title: Jet Spaces and Diophantine Problems

From playlist Spring 2014

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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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Introduction to elliptic curves and BSD Conjecture by Sujatha Ramadorai

12 December 2016 to 22 December 2016 VENUE Madhava Lecture Hall, ICTS Bangalore The Birch and Swinnerton-Dyer conjecture is a striking example of conjectures in number theory, specifically in arithmetic geometry, that has abundant numerical evidence but not a complete general solution. An

From playlist Theoretical and Computational Aspects of the Birch and Swinnerton-Dyer Conjecture

Related pages

Elementary abelian group | Order (group theory) | Direct sum | Integral domain | Flat module | Vector space | Free abelian group | Mathematics | Torsion (algebra) | Tensor product | Finitely generated abelian group | Indecomposable module | Cardinality | Finitely generated module | Rank of a group | Abelian group | Module (mathematics) | Torsion subgroup