Why Normal Subgroups are Necessary for Quotient Groups
Proof that cosets are disjoint: https://youtu.be/uxhAUmgSHnI In order for a subgroup to create a quotient group (also known as factor group), it must be a normal subgroup. That means that when we conjugate an element in the subgroup, it stays in the subgroup. In this video, we explain wh
From playlist Group Theory
Permutation Groups and Symmetric Groups | Abstract Algebra
We introduce permutation groups and symmetric groups. We cover some permutation notation, composition of permutations, composition of functions in general, and prove that the permutations of a set make a group (with certain details omitted). #abstractalgebra #grouptheory We will see the
From playlist Abstract Algebra
The Conjugacy Class is of a is {a} iff a is in the Center of the Group Proof
Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys The Conjugacy Class is of a is {a} iff a is in the Center of the Group Proof
From playlist Abstract Algebra
AKPotW: Conjugates of a Subgroup [Group Theory]
If this video is confusing, be sure to check out our blog for the full solution transcript! https://centerofmathematics.blogspot.com/2018/06/advanced-knowledge-problem-of-week-6-28.html
From playlist Center of Math: Problems of the Week
Visual Group Theory, Lecture 3.7: Conjugacy classes
Visual Group Theory, Lecture 3.7: Conjugacy classes We were first introduced to the concept of conjugacy when studying normal subgroups: H is normal if every conjugate of H is equal to H. Alternatively, we can fix an element x of G, and ask: "which elements can be written as conjugates o
From playlist Visual Group Theory
Conjugate of products is product of conjugates
For all complex numbers, why is the conjugate of two products equal to the product of their conjugates? Basic example is discussed. Free ebook http://bookboon.com/en/introduction-to-complex-numbers-ebook
From playlist Intro to Complex Numbers
In this video we construct a symmetric group from the set that contains the six permutations of a 3 element group under composition of mappings as our binary operation. The specifics topics in this video include: permutations, sets, groups, injective, surjective, bijective mappings, onto
From playlist Abstract algebra
The idea of a quotient group follows easily from cosets and Lagrange's theorem. In this video, we start with a normal subgroup and develop the idea of a quotient group, by viewing each coset (together with the normal subgroup) as individual mathematical objects in a set. This set, under
From playlist Abstract algebra
In this veideo we continue our look in to the dihedral groups, specifically, the dihedral group with six elements. We note that two of the permutation in the group are special in that they commute with all the other elements in the group. In the next video I'll show you that these two el
From playlist Abstract algebra
Visual Group Theory, Lecture 5.3: Examples of group actions
Visual Group Theory, Lecture 5.3: Examples of group actions It is frequently of interest to analyze the action of a group on its elements (by multiplication), subgroups (by multiplication, or by conjugation), or cosets (by multiplication). We look at all of these, and analyze the orbits,
From playlist Visual Group Theory
Group theory 22: Symmetric groups
This lecture is part of an online mathematics course on group theory. It covers the basic theory of symmetric and alternating groups, in particular their conjugacy classes.
From playlist Group theory
GT18.2. A_n is Simple (n ge 5)
Abstract Algebra: Using conjugacy classes, we give a second proof that A5, the alternating group on 5 letters, is simple. We adapt the first proof that A5 is simple to show that An is simple when n is greater than 5. The key step is to show that any normal subgroup with more than the id
From playlist Abstract Algebra
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
GT17. Symmetric and Alternating Groups
EDIT: at 15:00, we have (abcde) = (abc)(cde) instead of (abc)(ade) Abstract Algebra: We review symmetric and alternating groups. We show that S_n is generated by its 2-cycles and that A_n is generated by its 3-cycles. Applying the latter with the Conjugation Formula, we show that A_5 i
From playlist Abstract Algebra
GT20. Overview of Sylow Theory
Abstract Algebra: As an analogue of Cauchy's Theorem for subgroups, we state the three Sylow Theorems for finite groups. Examples include S3 and A4. We also note the analogue to Sylow Theory for p-groups. U.Reddit course materials available at http://ureddit.com/class/23794/intro-to-gr
From playlist Abstract Algebra
Bettina EICK - Computational group theory, cohomology of groups and topological methods 1
The lecture series will give an introduction to the computer algebra system GAP, focussing on calculations involving cohomology. We will describe the mathematics underlying the algorithms, and how to use them within GAP. Alexander Hulpke's lectures will being with some general computation
From playlist École d'Été 2022 - Cohomology Geometry and Explicit Number Theory
Stability of amenable groups via ergodic theory - Arie Levit
Stability and Testability Topic: Stability of amenable groups via ergodic theory Speaker: Arie Levit Affiliation: Yale University Date: January 27, 2021 For more video please visit http://video.ias.edu
From playlist Stability and Testability
Class Equation for Dihedral Group D8
EDIT: At 3:30, switch lines in point 5. Abstract Algebra: Consider the dihedral group with eight elements D8, the symmetries of the square. Find all conjugacy classes of D8, and verify the class equation. Then find all subgroups and determine which ones are normal.
From playlist Abstract Algebra
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