Algebraic groups

Diagonalizable group

In mathematics, an affine algebraic group is said to be diagonalizable if it is isomorphic to a subgroup of Dn, the group of diagonal matrices. A diagonalizable group defined over a field k is said to split over k or k-split if the isomorphism is defined over k. This coincides with the usual notion of split for an algebraic group. Every diagonalizable group splits over the separable closure ks of k. Any closed subgroup and image of diagonalizable groups are diagonalizable. The torsion subgroup of a diagonalizable group is dense. The category of diagonalizable groups defined over k is equivalent to the category of finitely generated abelian groups with Gal(ks/k)-equivariant morphisms without p-torsion, if k is of characteristic p. This is an analog of Poincaré duality and motivated the terminology. A diagonalizable k-group is said to be anisotropic if it has no nontrivial k-valued character. The so-called "rigidity" states that the identity component of the centralizer of a diagonalizable group coincides with the identity component of the normalizer of the group. The fact plays a crucial role in the structure theory of solvable groups. A connected diagonalizable group is called an algebraic torus (which is not necessarily compact, in contrast to a complex torus). A k-torus is a torus defined over k. The centralizer of a maximal torus is called a Cartan subgroup. (Wikipedia).

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Diagonalizability

Characterizations of Diagonalizability In this video, I define the notion of diagonalizability and show what it has to do with eigenvectors. Check out my Diagonalization playlist: https://www.youtube.com/playlist?list=PLJb1qAQIrmmCSovHY6cXzPMNSuWOwd9wB Subscribe to my channel: https://

From playlist Diagonalization

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The Diagonalization of Matrices

This video explains the process of diagonalization of a matrix.

From playlist The Diagonalization of Matrices

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Diagonal Matrices

This video defines a diagonal matrix and then explains how to determine the inverse of a diagonal matrix (if possible) and how to raise a diagonal matrix to a power. Site: mathispower4u.com Blog: mathispower4u.wordpress.com

From playlist Introduction to Matrices and Matrix Operations

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Math 060 Fall 2017 112217C Diagonalization Part 2

Review: the matrix representation of a matrix with respect to an eigenvector basis is a diagonal matrix of eigenvalues. Definition: diagonalizable matrix. Alternate proof of the fact that a matrix is diagonalizable iff there exists an eigenvector basis. Exercise: diagonalize a matrix.

From playlist Course 4: Linear Algebra (Fall 2017)

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Block Diagonal Matrices

Every operator on a finite-dimensional complex vector space has a matrix (with respect to some basis of the vector space) that is a block diagonal matrix, with each block itself an upper-triangular matrix that contains only one eigenvalue on the diagonal.

From playlist Linear Algebra Done Right

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Linear Algebra - Lecture 35 - Diagonalizable Matrices

In this lecture, we discuss what it means for a square matrix to be diagonalizable. We prove the Diagonalization Theorem, which tells us exactly when a matrix is diagonalizable.

From playlist Linear Algebra Lectures

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Florian Herzig: On de Rham lifts of local Galois representations

Find other talks given by worldwide mathematicians on CIRM's Audiovisual Mathematics Library: http://library.cirm-math.fr. And discover all its functionalities: - Chapter markers and keywords to watch the parts of your choice in the video - Videos enriched with abstracts, bibliographies,

From playlist Algebraic and Complex Geometry

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Linear Algebra - Lecture 36 - Diagonalizing a Matrix

In this lecture, we work through some examples where we attempt to diagonalize a matrix. We also discuss a sufficient (but not necessary) condition for diagonalizability.

From playlist Linear Algebra Lectures

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This Hard Linear Algebra Exam Crushed OVER 90% of All FIRST YEARS?!

All my Merch can be found here! =) https://teespring.com/stores/papaflammy Wanna send me your hard exams? Here you go: piequals3@papaflammy.engineer Hard Exam Playlist: https://www.youtube.com/watch?v=5mHkCEHfGSg&list=PLN2B6ZNu6xmeiEFInOyQWJ3siUK9VRnrd Solving Hard Exams: https://www.youtu

From playlist Hard Exams Gone Wrong

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Automorphy: Deformations of Galois Representations - David Geraghty

David Geraghty Institute for Advanced Study February 24, 2011 For more videos, visit http://video.ias.edu

From playlist Mathematics

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Product groups

Now that we have defined and understand quotient groups, we need to look at product groups. In this video I define the product of two groups as well as the group operation, proving that it is indeed a group.

From playlist Abstract algebra

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Galois theory: Kummer extensions

This lecture is part of an online graduate course on Galois theory. We describe Galois extensions with cyclic Galois group of order n in the case when the base field contains all n'th roots of unity and has characteristic not dividing n. We show that all such extensions are radical. As an

From playlist Galois theory

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Lie Groups and Lie Algebras: Lesson 10: The Classical Groups part VIII

Lie Groups and Lie Algebras: Lesson 10: The Classical Groups part VIII In this lecture we demonstrate the canonical form of a bilinear symmetric metric. This will help us appreciate that all of the most important types of metrics can be represented by matrices of a specific "canonical" ty

From playlist Lie Groups and Lie Algebras

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Potential Automorphy for Compatible Systems of l-Adic Galois Representations - David Geraghty

David Geraghty Princeton University; Member, School of Mathematics November 18, 2010 I will describe a joint work with Barnet-Lamb, Gee and Taylor where we establish a potential automorphy result for compatible systems of Galois representations over totally real and CM fields. This is ded

From playlist Mathematics

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Direct Sum

Direct Sum definition In this video, I define the notion of direct sum of n subspaces and show what it has to do with eigenvectors. Direct sum of two subspaces: https://youtu.be/GjbMddz0Qxs Check out my Diagonalization playlist: https://www.youtube.com/playlist?list=PLJb1qAQIrmmCSovHY6c

From playlist Diagonalization

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Felix Klein Lectures 2020: Quiver moduli and applications, Markus Reineke (Bochum), Lecture 2

Quiver moduli spaces are algebraic varieties encoding the continuous parameters of linear algebra type classification problems. In recent years their topological and geometric properties have been explored, and applications to, among others, Donaldson-Thomas and Gromov-Witten theory have

From playlist Felix Klein Lectures 2020: Quiver moduli and applications, Markus Reineke (Bochum)

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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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Diagonalization

Now that we know about eigenvalues and eigenvectors, we are ready to learn about diagonalization. This involves writing a matrix as a product of other matrices, one of which is a diagonal matrix, with values only along the main diagonal. This has many applications in computation, so let's

From playlist Mathematics (All Of It)

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Persi Diaconis - From Shuffling Cards to Walking Around the Building [ICM 1998]

ICM Berlin Videos 27.08.1998 From Shuffling Cards to Walking Around the Building Persi Diaconis Mathematics and ORIE, Cornell University, Ithaca, USA: Statistics, Probability, Algebraic Combinatorics Thu 27-Aug-98 · 14:00-15:00 h Abastract: https://www.mathunion.org/fileadmin/IMU/Video

From playlist Number Theory

Related pages

Poincaré duality | Subgroup | Diagonal subgroup | Characteristic (algebra) | Mathematics | Solvable group | Field (mathematics) | Cartan subgroup | Complex torus | Equivalence of categories | Finitely generated abelian group | Category (mathematics) | Algebraic torus | Splitting lemma | Torsion subgroup