Abstract algebra | Symmetry | Morphisms
In mathematics, an automorphism is an isomorphism from a mathematical object to itself. It is, in some sense, a symmetry of the object, and a way of mapping the object to itself while preserving all of its structure. The set of all automorphisms of an object forms a group, called the automorphism group. It is, loosely speaking, the symmetry group of the object. (Wikipedia).
Group automorphisms in abstract algebra
Group automorphisms are bijective mappings of a group onto itself. In this tutorial I define group automorphisms and introduce the fact that a set of such automorphisms can exist. This set is proven to be a subgroup of the symmetric group. You can learn more about Mathematica on my Udem
From playlist Abstract algebra
Abstract Algebra - 6.5 Automorphisms
We finish up chapter 6 by discussion automorphisms and inner automorphisms. An automorphism is just a special isomorphism that maps a group to itself. An inner-automorphism uses conjugation of an element and its inverse to create a mapping. Video Chapters: Intro 0:00 What is an Automorphi
From playlist Abstract Algebra - Entire Course
Homomorphisms in abstract algebra
In this video we add some more definition to our toolbox before we go any further in our study into group theory and abstract algebra. The definition at hand is the homomorphism. A homomorphism is a function that maps the elements for one group to another whilst maintaining their structu
From playlist Abstract algebra
Graph Theory FAQs: 02. Graph Automorphisms
An automorphism of a graph G is an isomorphism between G and itself. The set of automorphisms of a graph forms a group under the operation of composition and is denoted Aut(G). The automorphisms of a graph describe the symmetries of the graph. We look at a few examples of graphs and det
From playlist Graph Theory FAQs
In this tutorial I present the cyclic group of three elements as a group automorphism. You can learn more about Mathematica on my Udemy courses: https://www.udemy.com/mathematica/ https://www.udemy.com/mathematica-for-statistics/
From playlist Abstract algebra
Isomorphisms in abstract algebra
In this video I take a look at an example of a homomorphism that is both onto and one-to-one, i.e both surjective and injection, which makes it a bijection. Such a homomorphism is termed an isomorphism. Through the example, I review the construction of Cayley's tables for integers mod 4
From playlist Abstract algebra
Visual Group Theory, Lecture 6.2: Field automorphisms
Visual Group Theory, Lecture 6.2: Field automorphisms A field automorphism is a structure preserving map from a field F to itself. This means that it must be both a homomorphism of both the addtive group (F,+) and the multiplicative group (F-{0},*). We show that any automorphism of an ext
From playlist Visual Group Theory
Complex Analysis: Conformal Automorphisms are Linear!
Today, we prove a theorem that all conformal automorphisms of the complex plane are linear mappings. Casorati Weierstrass Theorem: Part 1 (intro): https://youtu.be/hzZOR-8ETyA Part 2 (proof): https://youtu.be/HfnZrAx5FTo
From playlist Complex Analysis
Isomorphisms (Abstract Algebra)
An isomorphism is a homomorphism that is also a bijection. If there is an isomorphism between two groups G and H, then they are equivalent and we say they are "isomorphic." The groups may look different from each other, but their group properties will be the same. Be sure to subscribe s
From playlist Abstract Algebra
Jason Parker - Covariant Isotropy of Grothendieck Toposes
Talk at the school and conference “Toposes online” (24-30 June 2021): https://aroundtoposes.com/toposesonline/ Slides: https://aroundtoposes.com/wp-content/uploads/2021/07/ParkerSlidesToposesOnline.pdf Covariant isotropy can be regarded as providing an abstract notion of conjugation or i
From playlist Toposes online
Galois theory: Frobenius automorphism
This lecture is part of an online graduate course on Galois theory. We show that the Frobenius automorphism of a finite field an sometimes be lifted to characteristic 0. As an example we use the Frobenius automorphisms of Q[i] to prove that -1 i a square mod an odd prime p if and only if
From playlist Galois theory
Zlil Sela - Automorphisms of groups and a higher rank JSJ decomposition
The JSJ (for groups) was originally constructed to study the automorphisms and the cyclic splittings of a (torsion-free) hyperbolic group. Such a structure theory was needed to complete the solution of the isomorphism problem for (torsion-free) hyperbolic groups. Later, the JSJ was genera
From playlist Geometry in non-positive curvature and Kähler groups
Visual Group Theory, Lecture 4.6: Automorphisms
Visual Group Theory, Lecture 4.6: Automorphisms An automorphism is an isomorphism from a group to itself. The set of all automorphisms of G forms a group under composition, denoted Aut(G). After a few simple examples, we learn how Aut(Z_n) is isomorphic to U(n), which is the group consist
From playlist Visual Group Theory
Group theory 30: Outer automorphisms
This lecture is part of an online course on group theory. We find the automorphism groups of symmetric groups, and in particular show that the symmetric group on 6 points has "extra" (outer) automorphisms.
From playlist Group theory
Alexander HULPKE - Computational group theory, cohomology of groups and topological methods 5
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
Non-amenable groups admitting no sofic approximation by expander graphs - Gabor Kun
Stability and Testability Topic: Non-amenable groups admitting no sofic approximation by expander graphs Speaker: Gabor Kun Affiliation: Alfréd Rényi Institute of Mathematics Date: February 10, 2021 For more video please visit http://video.ias.edu
From playlist Stability and Testability
Karen Vogtmann: The geometry and topology of automorphism groups of free groups
HYBRID EVENT Recorded during the meeting "Groups Acting on Fractals" the April 11, 2022 by the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual Ma
From playlist Topology
Differential Isomorphism and Equivalence of Algebraic Varieties Board at 49:35 Sum_i=1^N 2/(x-phi_i(y,t))^2
From playlist Fall 2017
Homomorphisms in abstract algebra examples
Yesterday we took a look at the definition of a homomorphism. In today's lecture I want to show you a couple of example of homomorphisms. One example gives us a group, but I take the time to prove that it is a group just to remind ourselves of the properties of a group. In this video th
From playlist Abstract algebra