Properties of groups

Simple group

In mathematics, a simple group is a nontrivial group whose only normal subgroups are the trivial group and the group itself. A group that is not simple can be broken into two smaller groups, namely a nontrivial normal subgroup and the corresponding quotient group. This process can be repeated, and for finite groups one eventually arrives at uniquely determined simple groups, by the Jordan–Hölder theorem. The complete classification of finite simple groups, completed in 2004, is a major milestone in the history of mathematics. (Wikipedia).

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Definition of a group Lesson 24

In this video we take our first look at the definition of a group. It is basically a set of elements and the operation defined on them. If this set of elements and the operation defined on them obey the properties of closure and associativity, and if one of the elements is the identity el

From playlist Abstract algebra

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Simple Groups - Abstract Algebra

Simple groups are the building blocks of finite groups. After decades of hard work, mathematicians have finally classified all finite simple groups. Today we talk about why simple groups are so important, and then cover the four main classes of simple groups: cyclic groups of prime order

From playlist Abstract Algebra

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From playlist Modern Algebra - Chapter 15 (groups)

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Quotient group example

Now that we know what a quotient group is, let's take a look at an example to cement our understanding of the concepts involved.

From playlist Abstract algebra

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From playlist Abstract Algebra

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Chapter 5: Quotient groups | Essence of Group Theory

Quotient groups is a very important concept in group theory, because it has paramount importance in group homomorphisms (connection with the isomorphism theorem(s)). With this video series, abstract algebra needs not be abstract - one can easily develop intuitions for group theory! In fac

From playlist Essence of Group Theory

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From playlist MathHistory: A course in the History of Mathematics

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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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Product groups

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From playlist Abstract algebra

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From playlist Visual Group Theory

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Sporadic groups

This is an informal talk on sporadic groups given to the Archimedeans (the Cambridge undergraduate mathematical society). It discusses the classification of finite simple groups and some of the sporadic groups, and finishes by briefly describing monstrous moonshine. For other Archimedeans

From playlist Math talks

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Group theory 29:The Jordan Holder theorem

This lecture is part of an online course on group theory. It covers the Jordan-Holder theorem, staring that the simple groups appearing in a composition series of a finite group do not depend on the composition series.

From playlist Group theory

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Representation theory and geometry – Geordie Williamson – ICM2018

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From playlist Plenary Lectures

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From playlist Abstract Algebra

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Imprimitive irreducible representations of finite quasisimple groups by Gerhard Hiss

DATE & TIME 05 November 2016 to 14 November 2016 VENUE Ramanujan Lecture Hall, ICTS Bangalore Computational techniques are of great help in dealing with substantial, otherwise intractable examples, possibly leading to further structural insights and the detection of patterns in many abstra

From playlist Group Theory and Computational Methods

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Regular permutation groups and Cayley graphs

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From playlist PRIMA2009

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Geometric Categorifications of the Hecke Algebra - Laura Rider

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From playlist Mathematics

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Visual Group Theory, Lecture 1.6: The formal definition of a group

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From playlist Visual Group Theory

Related pages

Sporadic group | Order (group theory) | Galois theory | Monster group | Torsion (algebra) | Classical group | Finite field | Up to | Group (mathematics) | Isomorphism | Burnside's theorem | Permutation | Almost simple group | Tits group | Sylow theorems | Trivial group | Quasithin group | Group isomorphism | Alternating group | Mathieu group | Quotient group | Finite group | Subquotient | Composition series | Classification of finite simple groups | Mathematics | Modular arithmetic | Integer | Janko group | Modulo operation | Pariah group | Divisor | Characteristically simple group | Cyclic group | Normal subgroup | Quasisimple group | Thompson groups | E6 (mathematics) | List of finite simple groups | Prime number | Feit–Thompson theorem | Schreier conjecture | Claude Chevalley | Higman group | Griess algebra | Camille Jordan | Solvable group | Field with one element | PSL(2,7) | Abelian group | Center (group theory)