Ring theory

Division ring

In algebra, a division ring, also called a skew field, is a nontrivial ring in which division by nonzero elements is defined. Specifically, it is a nontrivial ring in which every nonzero element a has a multiplicative inverse, that is, an element usually denoted a–1, such that a a–1 = a–1 a = 1. So, (right) division may be defined as a / b = a b–1, but this notation is avoided, as one may have a b–1 ≠ b–1 a. A commutative division ring is a field. Wedderburn's little theorem asserts that all finite division rings are commutative and therefore finite fields. Historically, division rings were sometimes referred to as fields, while fields were called "commutative fields". In some languages, such as French, the word equivalent to "field" ("corps") is used for both commutative and noncommutative cases, and the distinction between the two cases is made by adding qualificatives such as "corps commutatif" (commutative field) or "corps gauche" (skew field). All division rings are simple. That is, they have no two-sided ideal besides the zero ideal and itself. (Wikipedia).

Video thumbnail

Units in a Ring (Abstract Algebra)

The units in a ring are those elements which have an inverse under multiplication. They form a group, and this “group of units” is very important in algebraic number theory. Using units you can also define the idea of an “associate” which lets you generalize the fundamental theorem of ar

From playlist Abstract Algebra

Video thumbnail

Definition of a Ring and Examples of Rings

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Definition of a Ring and Examples of Rings - Definition of a Ring. - Definition of a commutative ring and a ring with identity. - Examples of Rings include: Z, Q, R, C under regular addition and multiplication The Ring of all n x

From playlist Abstract Algebra

Video thumbnail

Ring Definition (expanded) - Abstract Algebra

A ring is a commutative group under addition that has a second operation: multiplication. These generalize a wide variety of mathematical objects like the integers, polynomials, matrices, modular arithmetic, and more. In this video we will take an in depth look at the definition of a rin

From playlist Abstract Algebra

Video thumbnail

Abstract Algebra | Types of rings.

We define several and give examples of different types of rings which have additional structure. http://www.michael-penn.net http://www.randolphcollege.edu/mathematics/

From playlist Abstract Algebra

Video thumbnail

RNT1.1. Definition of Ring

Ring Theory: We define rings and give many examples. Items under consideration include commutativity and multiplicative inverses. Example include modular integers, square matrices, polynomial rings, quaternions, and adjoins of algebraic and transcendental numbers.

From playlist Abstract Algebra

Video thumbnail

RNT1.4. Ideals and Quotient Rings

Ring Theory: We define ideals in rings as an analogue of normal subgroups in group theory. We give a correspondence between (two-sided) ideals and kernels of homomorphisms using quotient rings. We also state the First Isomorphism Theorem for Rings and give examples.

From playlist Abstract Algebra

Video thumbnail

Abstract Algebra: The definition of a Ring

Learn the definition of a ring, one of the central objects in abstract algebra. We give several examples to illustrate this concept including matrices and polynomials. Be sure to subscribe so you don't miss new lessons from Socratica: http://bit.ly/1ixuu9W ♦♦♦♦♦♦♦♦♦♦ We recommend th

From playlist Abstract Algebra

Video thumbnail

Ring Examples (Abstract Algebra)

Rings are one of the key structures in Abstract Algebra. In this video we give lots of examples of rings: infinite rings, finite rings, commutative rings, noncommutative rings and more! Be sure to subscribe so you don't miss new lessons from Socratica: http://bit.ly/1ixuu9W ♦♦♦♦♦♦♦♦♦

From playlist Abstract Algebra

Video thumbnail

Rings and midules 3: Burnside ring and rings of differential operators

This lecture is part of an online course on rings and modules. We discuss a few assorted examples of rings. The Burnside ring of a group is a ring constructed form the permutation representations. The ring of differentail operators is a ring whose modules are related to differential equat

From playlist Rings and modules

Video thumbnail

What is a Tensor? Lesson 19: Algebraic Structures I

What is a Tensor? Lesson 19: Algebraic Structures Part One: Groupoids to Fields This is a redo or a recently posted lesson. Same content, a bit cleaner. Algebraic structures are frequently mentioned in the literature of general relativity, so it is good to understand the basic lexicon of

From playlist What is a Tensor?

Video thumbnail

Rings and modules 4 Unique factorization

This lecture is part of an online course on rings and modules. We discuss unique factorization in rings, showing the implications (Integers) implies (Euclidean domain) implies (Principal ideal domain) implies (Unique factorization domain). We give a few examples to illustrate these implic

From playlist Rings and modules

Video thumbnail

The importance of Being in Shape - Lecture 2 by Ramanujam Srinivasan

ORGANIZERS : Vidyanand Nanjundiah and Olivier Rivoire DATE & TIME : 16 April 2018 to 26 April 2018 VENUE : Ramanujan Lecture Hall, ICTS Bangalore This program is aimed at Master's- and PhD-level students who wish to be exposed to interesting problems in biology that lie at the biology-

From playlist Living Matter 2018

Video thumbnail

Nihar Gargava - Random lattices as sphere packings

In 1945, Siegel showed that the expected value of the lattice-sums of a function over all the lattices of unit covolume in an n-dimensional real vector space is equal to the integral of the function. In 2012, Venkatesh restricted the lattice- sum function to a collection of lattices that h

From playlist Combinatorics and Arithmetic for Physics: Special Days 2022

Video thumbnail

[ANT01] Algebraic number theory: an introduction, via Fermat's last theorem

The existence of the Euclidean algorithm is what makes multiplication in Z so nice. But some other rings have Euclidean algorithms too. Here's how we can exploit this for profit.

From playlist [ANT] An unorthodox introduction to algebraic number theory

Video thumbnail

Biology and Reconstitution of Minimalistic Systems by R Srinivasan

DISCUSSION MEETING : THIRSTING FOR THEORETICAL BIOLOGY ORGANIZERS : Vijaykumar Krishnamurthy and Vidyanand Nanjundiah DATE : 03 June 2019 to 07 June 2019 VENUE : Ramanujan Lecture Hall, ICTS Bangalore Experimental biologists frequently point out that theoreticians trivialise th

From playlist Thirsting for Theoretical Biology 2019

Video thumbnail

Rings and modules 2: Group rings

This lecture is part of an online course on rings and modules. We decribe some examples of rings constructed from groups and monoids, such as group rings and rings of Dirichlet polynomials. For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj52XDLrm

From playlist Rings and modules

Video thumbnail

Visual Group Theory, Lecture 7.1: Basic ring theory

Visual Group Theory, Lecture 7.1: Basic ring theory A ring is an abelian group (R,+) with a second binary operation, multiplication and the distributive law. Multiplication need not commute, nor need there be multiplicative inverses, so a ring is like a field but without these properties.

From playlist Visual Group Theory

Related pages

Invariant basis number | Simple ring | Vector space | Finite field | Linear algebra | Zero ring | Ideal (ring theory) | Hua's identity | Automorphism | Near-field (mathematics) | Quaternion | Emil Artin | Identity function | Rational number | Frobenius theorem (real division algebras) | Gaussian elimination | Algebra | Free module | Division (mathematics) | Schur's lemma | Field (mathematics) | Octonion | Simple module | Wedderburn's little theorem | Real number | Ring (mathematics) | Endomorphism ring | Complex conjugate | Complex number | Division algebra | Matrix (mathematics) | Module (mathematics) | Multiplicative inverse