Group theory

Direct sum of groups

In mathematics, a group G is called the direct sum of two normal subgroups with trivial intersection if it is generated by the subgroups. In abstract algebra, this method of construction of groups can be generalized to direct sums of vector spaces, modules, and other structures; see the article direct sum of modules for more information. A group which can be expressed as a direct sum of non-trivial subgroups is called decomposable, and if a group cannot be expressed as such a direct sum then it is called indecomposable. (Wikipedia).

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Finding the Right Cosets of a Subgroup of the Direct Product Z_3 x Z_2

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Finding the Right Cosets of a Subgroup of the Direct Product Z_3 x Z_2

From playlist Abstract Algebra

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Abstract Algebra | Direct product of groups.

We determine when the direct product of cyclic groups is cyclic. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Abstract Algebra

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Direct Sum

Direct Sum definition In this video, I define the notion of direct sum of n subspaces and show what it has to do with eigenvectors. Direct sum of two subspaces: https://youtu.be/GjbMddz0Qxs Check out my Diagonalization playlist: https://www.youtube.com/playlist?list=PLJb1qAQIrmmCSovHY6c

From playlist Diagonalization

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Direct Sum

Have you ever wondered how to sum two mathematical objects in an elegant way? Then this video is for you! In this video, I define the sum of two vector spaces and show something neat: If you add two bases together, you get a basis for the direct sum! Finally, I generalize this notion to di

From playlist Vector Spaces

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Product groups

Now that we have defined and understand quotient groups, we need to look at product groups. In this video I define the product of two groups as well as the group operation, proving that it is indeed a group.

From playlist Abstract algebra

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Abstract Algebra | Internal direct product of subgroups.

We give the definition of an internal direct product of subgroups, prove a result, and give some examples. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Abstract Algebra

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Find the Quotient Group (Z_3 x Z_2)/({0} x Z_2) Example with Direct Product

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Find the Quotient Group (Z_3 x Z_2)/({0} x Z_2) Example with Direct Product

From playlist Abstract Algebra

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Visual Group Theory, Lecture 3.5: Quotient groups

Visual Group Theory, Lecture 3.5: Quotient groups Like how a direct product can be thought of as a way to "multiply" two groups, a quotient is a way to "divide" a group by one of its subgroups. We start by defining this in terms of collapsing Cayley diagrams, until we get a conjecture abo

From playlist Visual Group Theory

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Direct Products of Groups (Abstract Algebra)

The direct product is a way to combine two groups into a new, larger group. Just as you can factor integers into prime numbers, you can break apart some groups into a direct product of simpler groups. Be sure to subscribe so you don't miss new lessons from Socratica: http://bit.ly/1ixuu

From playlist Abstract Algebra

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The Math You Didn't Learn | #SoME2

Sometimes people wonder what actual mathematicians do. Do they crunch large numbers? Participate in competitions with each other? (They actually did a lot of that in the Middle Ages). Are they geniuses whose activites are unfathomable for us normal people? Math is a very large field, but m

From playlist Summer of Math Exposition 2 videos

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What is a Tensor? Lesson 20: Algebraic Structures II - Modules to Algebras

What is a Tensor? Lesson 20: Algebraic Structures II - Modules to Algebras We complete our survey of the basic algebraic structures that appear in the study of general relativity. Also, we develop the important example of the tensor algebra.

From playlist What is a Tensor?

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Introduction to geometric invariant theory 1: Noncommutative duality - Ankit Garg

Optimization, Complexity and Invariant Theory Topic: Introduction to geometric invariant theory 1: Noncommutative duality Speaker: Ankit Garg Affiliation: Microsoft Research New England Date: June 5. 2018 For more videos, please visit http://video.ias.edu

From playlist Mathematics

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Lie Groups and Lie Algebras: Lesson 41: Elementary Representation Theory I

Lie Groups and Lie Algebras: Lesson 41: Elementary Representation Theory I I wanted to begin a more intricate example of the principle of a Universal Covering group, but I think I need to cover a little background material. We need to get a grip on what is meant by "Representation Theory"

From playlist Lie Groups and Lie Algebras

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Yonatan Harpaz - New perspectives in hermitian K-theory I

For questions and discussions of the lecture please go to our discussion forum: https://www.uni-muenster.de/TopologyQA/index.php?qa=k%26l-conference This lecture is part of the event "New perspectives on K- and L-theory", 21-25 September 2020, hosted by Mathematics Münster: https://go.wwu

From playlist New perspectives on K- and L-theory

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Representation Theory & Categorification - Catharina Stroppel

2021 Women and Mathematics - Uhlenbeck Course Lecture Topic: Representation Theory & Categorification Speaker: Catharina Stroppel Affiliation: University of Bonn Date: May 24, 2021 For more video please visit https://www.ias.edu/video

From playlist Mathematics

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Rings 10 Tensor products of abelian groups

This lecture is part of an online course on rings and modules. We define tensor products of abelian groups, and calculate them for many common examples using the fact that tensor products preserve colimits. For the other lectures in the course see https://www.youtube.com/playlist?list=P

From playlist Rings and modules

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Norm Minimization, Invariant Theory, and the Jacobian conjecture - William Cole Franks

Computer Science/Discrete Mathematics Seminar II Topic: Norm Minimization, Invariant Theory, and the Jacobian conjecture Speaker: William Cole Franks Affiliation: Massachusetts Institute of Technology Date: January 18, 2022 Consider the action of a group on a finite-dimensional vector sp

From playlist Mathematics

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Group theory 7: Semidirect products

This is lecture 7 of an online course on group theory. It covers semidirect products and uses them to classify groups of order 6.

From playlist Group theory

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Ben Elias: Categorifying Hecke algebras at prime roots of unity

Thirty years ago, Soergel changed the paradigm with his algebraic construction of the Hecke category. This is a categorification of the Hecke algebra at a generic parameter, where the parameter is categorified by a grading shift. One key open problem in categorification is to categorify He

From playlist Workshop: Monoidal and 2-categories in representation theory and categorification

Related pages

Vector space | Divisible group | Direct sum of modules | Free product | Coproduct | Isomorphism | Group (mathematics) | Identity element | Trivial group | Generating set of a group | Direct sum of topological groups | Direct product of groups | Mathematics | Normal subgroup | Cartesian product | Direct sum | Subgroup | Abstract algebra | Module (mathematics)