Sporadic groups

Conway group

In the area of modern algebra known as group theory, the Conway groups are the three sporadic simple groups Co1, Co2 and Co3 along with the related finite group Co0 introduced by (Conway , ). The largest of the Conway groups, Co0, is the group of automorphisms of the Leech lattice Λ with respect to addition and inner product. It has order 8,315,553,613,086,720,000 but it is not a simple group. The simple group Co1 of order 4,157,776,806,543,360,000 = 221 · 39 · 54 · 72 · 11 · 13 · 23 is defined as the quotient of Co0 by its center, which consists of the scalar matrices ±1. The groups Co2 of order 42,305,421,312,000 = 218 · 36 · 53 · 7 · 11 · 23 and Co3 of order 495,766,656,000 = 210 · 37 · 53 · 7 · 11 · 23 consist of the automorphisms of Λ fixing a lattice vector of type 2 and type 3, respectively. As the scalar −1 fixes no non-zero vector, these two groups are isomorphic to subgroups of Co1. The inner product on the Leech lattice is defined as 1/8 the sum of the products of respective co-ordinates of the two multiplicand vectors; it is an integer. The square norm of a vector is its inner product with itself, always an even integer. It is common to speak of the type of a Leech lattice vector: half the square norm. Subgroups are often named in reference to the types of relevant fixed points. This lattice has no vectors of type 1. (Wikipedia).

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Symmetric Groups (Abstract Algebra)

Symmetric groups are some of the most essential types of finite groups. A symmetric group is the group of permutations on a set. The group of permutations on a set of n-elements is denoted S_n. Symmetric groups capture the history of abstract algebra, provide a wide range of examples in

From playlist Abstract Algebra

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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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Dihedral Group (Abstract Algebra)

The Dihedral Group is a classic finite group from abstract algebra. It is a non abelian groups (non commutative), and it is the group of symmetries of a regular polygon. This group is easy to work with computationally, and provides a great example of one connection between groups and geo

From playlist Abstract Algebra

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Group Definition (expanded) - Abstract Algebra

The group is the most fundamental object you will study in abstract algebra. Groups generalize a wide variety of mathematical sets: the integers, symmetries of shapes, modular arithmetic, NxM matrices, and much more. After learning about groups in detail, you will then be ready to contin

From playlist Abstract Algebra

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Cyclic Groups (Abstract Algebra)

Cyclic groups are the building blocks of abelian groups. There are finite and infinite cyclic groups. In this video we will define cyclic groups, give a list of all cyclic groups, talk about the name “cyclic,” and see why they are so essential in abstract algebra. Be sure to subscribe s

From playlist Abstract Algebra

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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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GT2. Definition of Subgroup

Abstract Algebra: We define the notion of a subgroup and provide various examples. We also consider cyclic subgroups and subgroups generated by subsets in a given group G. Example include A4 and D8. U.Reddit course materials available at http://ureddit.com/class/23794/intro-to-group-

From playlist Abstract Algebra

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Abstract Algebra | The dihedral group

We present the group of symmetries of a regular n-gon, that is the dihedral group D_n. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Abstract Algebra

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Group Theory: The Center of a Group G is a Subgroup of G Proof

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Group Theory: The Center of a Group G is a Subgroup of G Proof

From playlist Abstract Algebra

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The Legendary John Conway (1937-2020) - Numberphile Podcast

We pay tribute to John Horton Conway - with clips from the man himself, plus contributions from Siobhan Roberts, David Eisenbud, Colm Mulcahy and Tony Padilla. Genius at Play by Siobhan Roberts - https://amzn.to/34ExQ4I John Conway Numberphile Playlist - https://www.youtube.com/playlist?

From playlist The Numberphile Podcast

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Remembering John Conway - Part 1

Bay Area Artists and Mathematicians - BAAM! with Gathering 4 Gardner - G4G present Remembering John Conway Mathematician John Horton Conway died of COVID-19 on April 11, 2020. On April 25th, the Bay Area Artists and Mathematicians (BAAM!) hosted an informal Zoom session to share memories

From playlist Tributes & Commemorations

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Allison Moore - Essential Conway spheres and Floer homology via immersed curves

38th Annual Geometric Topology Workshop (Online), June 15-17, 2021 Allison Moore, Virginia Commonwealth University Title: Essential Conway spheres and Floer homology via immersed curves Abstract: We consider the problem of whether Dehn surgery along a knot in the three-sphere produces an

From playlist 38th Annual Geometric Topology Workshop (Online), June 15-17, 2021

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Remembering John Conway - Part 4

Bay Area Artists and Mathematicians - BAAM! with Gathering 4 Gardner - G4G present Remembering John Conway Mathematician John Horton Conway died of COVID-19 on April 11, 2020. On April 25th, the Bay Area Artists and Mathematicians (BAAM!) hosted an informal Zoom session to share memories

From playlist Tributes & Commemorations

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Remembering John Conway - Full Video

Bay Area Artists and Mathematicians - BAAM! with Gathering 4 Gardner - G4G present Remembering John Conway Mathematician John Horton Conway died of COVID-19 on April 11, 2020. On April 25th, the Bay Area Artists and Mathematicians (BAAM!) hosted an informal Zoom session to share memories

From playlist Tributes & Commemorations

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Questions and Answers 1

This is an experimental video where I give answers to the (mostly) mathematical questions asked by viewers.

From playlist Math talks

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The Genesis of Vertex Algebras

We have a guest for this very special video. Richard Borcherds (Berkeley) has contributed a video regarding the history of vertex algebras. This video was also posted on his channel and is included here as well with permission and to increase its reach. Subscribe to his channel: https:/

From playlist Vertex Operator Algebras

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A Tribute to Berlekamp, Conway, Guy, Graham, and Randi - G4G14 Apr 2022

In the long four years between G4G13 and G4G14, we lost some towering figures from the G4G community. It is hard for many of us to see how we can go on without them, but their legacy will live on. In this tribute session, we honor Elwyn Berlekamp, John Conway, Richard Guy, Ron Graham, and

From playlist G4G14 Videos

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Genesis of vertex algebras

This is a historical talk giving my recollections of how vertex algebras were discovered. It was requested by Michael Penn for his series of videos on vertex algebras https://www.youtube.com/playlist?list=PL22w63XsKjqyx2FFUywi_mz91Jtih52yX

From playlist Math talks

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Matrix Groups (Abstract Algebra)

Matrices are a great example of infinite, nonabelian groups. Here we introduce matrix groups with an emphasis on the general linear group and special linear group. The general linear group is written as GLn(F), where F is the field used for the matrix elements. The most common examples

From playlist Abstract Algebra

Related pages

Suzuki sporadic group | Order (group theory) | Monster group | G2 (mathematics) | Monstrous moonshine | Holomorph (mathematics) | Generalized permutation matrix | Conway group Co1 | John Horton Conway | Dot product | Quaternion | Leech lattice | Conway group Co2 | Higman–Sims group | Binary Golay code | Fischer group | Hall–Janko graph | Group theory | Conway group Co3 | Involution (mathematics) | Mathieu group M24 | Symmetric matrix | Dedekind eta function | Automorphism group | Transpose | Matrix (mathematics) | Conjugacy class | Module (mathematics)