Algebras

Algebra over a field

In mathematics, an algebra over a field (often simply called an algebra) is a vector space equipped with a bilinear product. Thus, an algebra is an algebraic structure consisting of a set together with operations of multiplication and addition and scalar multiplication by elements of a field and satisfying the axioms implied by "vector space" and "bilinear". The multiplication operation in an algebra may or may not be associative, leading to the notions of associative algebras and non-associative algebras. Given an integer n, the ring of real square matrices of order n is an example of an associative algebra over the field of real numbers under matrix addition and matrix multiplication since matrix multiplication is associative. Three-dimensional Euclidean space with multiplication given by the vector cross product is an example of a nonassociative algebra over the field of real numbers since the vector cross product is nonassociative, satisfying the Jacobi identity instead. An algebra is unital or unitary if it has an identity element with respect to the multiplication. The ring of real square matrices of order n forms a unital algebra since the identity matrix of order n is the identity element with respect to matrix multiplication. It is an example of a unital associative algebra, a (unital) ring that is also a vector space. Many authors use the term algebra to mean associative algebra, or unital associative algebra, or in some subjects such as algebraic geometry, unital associative commutative algebra. Replacing the field of scalars by a commutative ring leads to the more general notion of an . Algebras are not to be confused with vector spaces equipped with a bilinear form, like inner product spaces, as, for such a space, the result of a product is not in the space, but rather in the field of coefficients. (Wikipedia).

Video thumbnail

Field Definition (expanded) - Abstract Algebra

The field is one of the key objects you will learn about in abstract algebra. Fields generalize the real numbers and complex numbers. They are sets with two operations that come with all the features you could wish for: commutativity, inverses, identities, associativity, and more. They

From playlist Abstract Algebra

Video thumbnail

Algebra for beginners || Basics of Algebra

In this course you will learn about algebra which is ideal for absolute beginners. #Algebra is the branch of mathematics that helps in the representation of problems or situations in the form of mathematical expressions. It involves variables like x, y, z, and mathematical operations like

From playlist Algebra

Video thumbnail

Algebra for Beginners | Basics of Algebra

#Algebra is one of the broad parts of mathematics, together with number theory, geometry and analysis. In its most general form, algebra is the study of mathematical symbols and the rules for manipulating these symbols; it is a unifying thread of almost all of mathematics. Table of Conten

From playlist Linear Algebra

Video thumbnail

Intro to Functions

As part of the college algebra series, this Center of Math video will teach you the basics of functions, including how they're written and what they do.

From playlist Basics: College Algebra

Video thumbnail

Abstract Algebra: The definition of a Field

Learn the definition of a Field, one of the central objects in abstract algebra. We give several familiar examples and a more unusual example. ♦♦♦♦♦♦♦♦♦♦ Ways to support our channel: ► Join our Patreon : https://www.patreon.com/socratica ► Make a one-time PayPal donation: https://www

From playlist Abstract Algebra

Video thumbnail

AlgTopReview: An informal introduction to abstract algebra

This is a review lecture on some aspects of abstract algebra useful for algebraic topology. It provides some background on fields, rings and vector spaces for those of you who have not studied these objects before, and perhaps gives an overview for those of you who have. Our treatment is

From playlist Algebraic Topology

Video thumbnail

Abstract Algebra | What is a ring?

We give the definition of a ring and present some examples. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Abstract Algebra

Video thumbnail

Field Examples - Infinite Fields (Abstract Algebra)

Fields are a key structure in Abstract Algebra. Today we give lots of examples of infinite fields, including the rational numbers, real numbers, complex numbers and more. We also show you how to extend fields using polynomial equations and convergent sequences. Be sure to subscribe so y

From playlist Abstract Algebra

Video thumbnail

Field Theory: Definition/ Axioms

This video is about the basics axioms of fields.

From playlist Basics: Field Theory

Video thumbnail

On the notion of genus for division algebras and algebraic groups - Andrei Rapinchu

Joint IAS/Princeton University Number Theory Seminar Topic: On the notion of genus for division algebras and algebraic groups Speaker: Andrei Rapinchu Affiliation: University of Virginia Date: November 2, 2017 For more videos, please visit http://video.ias.edu

From playlist Mathematics

Video thumbnail

Julia Hartmann, University of Pennsylvania

Julia Hartmann, University of Pennsylvania Patching in differential algebra

From playlist Online Workshop in Memory of Ray Hoobler - April 30, 2020

Video thumbnail

Galois theory: Field extensions

This lecture is part of an online course on Galois theory. We review some basic results about field extensions and algebraic numbers. We define the degree of a field extension and show that a number is algebraic over a field if and only if it is contained in a finite extension. We use thi

From playlist Galois theory

Video thumbnail

algebraic geometry 30 The Ax Grothendieck theorem

This lecture is part of an online algebraic geometry course, based on chapter I of "Algebraic geometry" by Hartshorne. It covers the Ax-Grothendieck theorem, which states that an injective regular map between varieties is surjective. The proof uses a strange technique: first prove the resu

From playlist Algebraic geometry I: Varieties

Video thumbnail

Emmy Noether: breathtaking mathematics - Georgia Benkart

Celebrating Emmy Noether Topic: Emmy Noether: breathtaking mathematics Speaker: Georgia Benkart Affiliation: University of Wisconsin-Madison Date: Friday, May 6 By the mid 1920s, Emmy Noether had made fundamental contributions to commutative algebra and to the theory of invariants.

From playlist Celebrating Emmy Noether

Video thumbnail

FIT2.3.3. Algebraic Extensions

Field Theory: We define an algebraic extension of a field F and show that successive algebraic extensions are also algebraic. This gives a useful criterion for checking algberaic elements. We finish with algebraic closures.

From playlist Abstract Algebra

Video thumbnail

Xevi Guitart : Endomorphism algebras of geometrically split abelian surfaces over Q

CONFERENCE Recording during the thematic meeting : "COUNT, COmputations and their Uses in Number Theory" the February 28, 2023 at the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Jean Petit Find this video and other talks given by worldwide mathematici

From playlist JEAN MORLET CHAIR

Video thumbnail

Galois theory: Wedderburn's theorem

This lecture is part of an online graduate course on Galois theory. We prove Wedderburn's theorem that all finite division algebras are fields. The proof uses cyclotomic polynomials.

From playlist Galois theory

Video thumbnail

Commutative algebra 32 Zariski's lemma

This lecture is part of an online course on commutative algebra, following the book "Commutative algebra with a view toward algebraic geometry" by David Eisenbud. We state and prove Zariski's lemma: Any field that is a finitely generated algebra over a field is a finitely generated modu

From playlist Commutative algebra

Video thumbnail

Fields - Field Theory - Lecture 00

This is the first in a series of videos for my abstract algebra class during the 2020 shutdown. This lecture is intended to rapidly catch students up who are going to follow online and aren't from UVM. We are using Dummit and Foote.

From playlist Field Theory

Video thumbnail

Commutative algebra 61: Examples of regular local rings

This lecture is part of an online course on commutative algebra, following the book "Commutative algebra with a view toward algebraic geometry" by David Eisenbud. We give some examples of regular local rings. We first give an example of a regular local ring that is not geometrically regul

From playlist Commutative algebra

Related pages

Vector space | Associative algebra | Partially ordered set | Max-plus algebra | Identity element | Bilinear map | Eduard Study | Polynomial ring | Field extension | Flexible algebra | Scalar multiplication | Octonion | Square matrix | Real number | Euclidean space | Lie algebra | Holomorphic function | Basis (linear algebra) | Hilbert space | Complex number | Matrix multiplication | Jordan algebra | Field with one element | Binary operation | Module (mathematics) | Differential algebra | Linear subspace | Zero ring | Center (ring theory) | Ideal (ring theory) | Banach space | Split-biquaternion | Injective function | Free module | Linear map | Integer | Pushforward (differential) | Cross product | Interval (mathematics) | Einstein notation | Index notation | Matrix (mathematics) | Functional analysis | Identity matrix | Product (mathematics) | Polynomial | Banach algebra | C*-algebra | Homomorphism | Operator algebra | Dual number | Group ring | Complex plane | Mathematics | Set (mathematics) | Function (mathematics) | Incidence algebra | Algebraic geometry | Geometric algebra | Free algebra | Covariance and contravariance of vectors | Inner product space | Gröbner basis | Jacobi identity | Zariski's lemma | Alternative algebra | Commutative ring | Clifford algebra | Topological space | Algebraic structure | Direct sum of modules | Continuous function | Up to | Group (mathematics) | Isomorphism | Commutative algebra | Quaternion | Field (mathematics) | Ring homomorphism | Ring (mathematics) | Scalar (mathematics) | Mutation (algebra) | Bilinear form | Matrix addition | Non-associative algebra | Pullback (differential geometry) | Anticommutative property