Group automorphisms | Group theory

Power automorphism

In mathematics, in the realm of group theory, a power automorphism of a group is an automorphism that takes each subgroup of the group to within itself. It is worth noting that the power automorphism of an infinite group may not restrict to an automorphism on each subgroup. For instance, the automorphism on rational numbers that sends each number to its double is a power automorphism even though it does not restrict to an automorphism on each subgroup. Alternatively, power automorphisms are characterized as automorphisms that send each element of the group to some power of that element. This explains the choice of the term power. The power automorphisms of a group form a subgroup of the whole automorphism group. This subgroup is denoted as where is the group. A universal power automorphism is a power automorphism where the power to which each element is raised is the same. For instance, each element may go to its cube. Here are some facts about the powering index: * The powering index must be relatively prime to the order of each element. In particular, it must be relatively prime to the order of the group, if the group is finite. * If the group is abelian, any powering index works. * If the powering index 2 or -1 works, then the group is abelian. The group of power automorphisms commutes with the group of inner automorphisms when viewed as subgroups of the automorphism group. Thus, in particular, power automorphisms that are also inner must arise as conjugations by elements in the second group of the upper central series. (Wikipedia).

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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

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From playlist Abstract algebra

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From playlist Abstract Algebra - Entire Course

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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

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From playlist Basics: Group Theory

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Group Isomorphisms in Abstract Algebra

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From playlist Abstract Algebra

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From playlist Visual Group Theory

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Isomorphisms in abstract algebra

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From playlist Abstract algebra

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From playlist Abstract Algebra

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CTNT 2020 - Infinite Galois Theory (by Keith Conrad) - Lecture 1

The Connecticut Summer School in Number Theory (CTNT) is a summer school in number theory for advanced undergraduate and beginning graduate students, to be followed by a research conference. For more information and resources please visit: https://ctnt-summer.math.uconn.edu/

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From playlist Abstract Algebra

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CTNT 2022 - 100 Years of Chebotarev Density (Lecture 1) - by Keith Conrad

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From playlist CTNT 2022 - 100 Years of Chebotarev Density (by Keith Conrad)

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Alessandra Sarti: Topics on K3 surfaces - Lecture 5: Finite automorphism groups

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CTNT 2022 - An Introduction to Galois Representations (Lecture 3) - by Alvaro Lozano-Robledo

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From playlist CTNT 2022 - An Introduction to Galois Representations (by Alvaro Lozano-Robledo)

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P-Adic Automorphic Forms and (big) Igusa Varieties by Sean Howe

Program Recent developments around p-adic modular forms (ONLINE) ORGANIZERS: Debargha Banerjee (IISER Pune, India) and Denis Benois (University of Bordeaux, France) DATE: 30 November 2020 to 04 December 2020 VENUE: Online This is a follow up of the conference organized last year arou

From playlist Recent Developments Around P-adic Modular Forms (Online)

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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

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Group automorphism example

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

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A Short Course in Algebra and Number Theory - Fields

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Related pages

Order (group theory) | Subgroup | Automorphism group | Mathematics | Group theory | Automorphism | Conjugacy class | Abelian group | Inner automorphism | Group (mathematics)