Ordered groups | Ordered algebraic structures | Real algebraic geometry
In mathematics, an ordered field is a field together with a total ordering of its elements that is compatible with the field operations. The basic example of an ordered field is the field of real numbers, and every Dedekind-complete ordered field is isomorphic to the reals. Every subfield of an ordered field is also an ordered field in the inherited order. Every ordered field contains an ordered subfield that is isomorphic to the rational numbers. Squares are necessarily non-negative in an ordered field. This implies that the complex numbers cannot be ordered since the square of the imaginary unit i is −1. Finite fields cannot be ordered. Historically, the axiomatization of an ordered field was abstracted gradually from the real numbers, by mathematicians including David Hilbert, Otto Hölder and Hans Hahn. This grew eventually into the Artin–Schreier theory of ordered fields and formally real fields. (Wikipedia).
Definition of a Field In this video, I define the concept of a field, which is basically any set where you can add, subtract, add, and divide things. Then I show some neat properties that have to be true in fields. Enjoy! What is an Ordered Field: https://youtu.be/6mc5E6x7FMQ Check out
From playlist Real Numbers
Math 101 090817 Introduction to Analysis 04 Ordered fields
Ordered sets. Examples. Ordered fields. Properties of ordered fields.
From playlist Course 6: Introduction to Analysis (Fall 2017)
Ordered Fields In this video, I define the notion of an order (or inequality) and then define the concept of an ordered field, and use this to give a definition of R using axioms. Actual Construction of R (with cuts): https://youtu.be/ZWRnZhYv0G0 COOL Construction of R (with sequences)
From playlist Real Numbers
Orders on Sets: Part 1 - Partial Orders
This was recorded as supplemental material for Math 115AH at UCLA in the spring quarter of 2020. In this video, I discuss the concept and definition of a partial order.
From playlist Orders on Sets
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
The elements of a set can be ordered by a relation. Some relation cause proper ordering and some, partial ordering. Have a look at some examples.
From playlist Abstract algebra
Math 101 Introduction to Analysis 091415: Fields, Ordered Fields
Fields. Field axioms. Examples and non-examples of fields. Properties of fields. Ordered sets. Ordered fields. Properties of ordered fields.
From playlist Course 6: Introduction to Analysis
Set Theory (Part 11): Ordering of the Natural Numbers
Please feel free to leave comments/questions on the video and practice problems below! In this video, we utilize the definition of natural number to speak of ordering on the set of all natural numbers. In addition, the well-ordering principle and trichotomy law are proved.
From playlist Set Theory by Mathoma
Order of Elements in a Group | Abstract Algebra
We introduce the order of group elements in this Abstract Algebra lessons. We'll see the definition of the order of an element in a group, several examples of finding the order of an element in a group, and we will introduce two basic but important results concerning distinct powers of ele
From playlist Abstract Algebra
This lecture is part of an online graduate course on Galois theory. We use the theory of splitting fields to classify finite fields: there is one of each prime power order (up to isomorphism). We give a few examples of small order, and point out that there seems to be no good choice for
From playlist Galois theory
Introduction to number theory lecture 30. Fields in number theory
This lecture is part of my Berkeley math 115 course "Introduction to number theory" For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj53L8sMbzIhhXSAOpuZ1Fov8 We extend some of the results we proved about the integers mod p to more general fields.
From playlist Introduction to number theory (Berkeley Math 115)
Self-force and radiation reaction in general relativity by Adam Pound ( Lecture 6 )
PROGRAM SUMMER SCHOOL ON GRAVITATIONAL WAVE ASTRONOMY ORGANIZERS : Parameswaran Ajith, K. G. Arun and Bala R. Iyer DATE : 15 July 2019 to 26 July 2019 VENUE : Madhava Lecture Hall, ICTS Bangalore This school is part of the annual ICTS summer schools on gravitational-wave (GW) astronomy.
From playlist Summer School on Gravitational Wave Astronomy -2019
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
Galois theory: Examples of Galois extensions
This lecture is part of an online graduate course on Galois theory. We give several examples of Galois extensions, and work out the correspondence between subfields and subgroups explicitly.
From playlist Galois theory
Non-monogenic Division Fields of Elliptic Curves, Hanson Smith
Abstract: This talk will serve as an exposition of a recent preprint investigating the division fields of elliptic curves. In this work we show that for various positive integers n there exist of infinite families of elliptic curves over Q with n-division fields, Q(E[n]), that are not mono
From playlist My Students
Álvaro Lozano-Robledo: Recent progress in the classification of torsion subgroups of...
Abstract: This talk will be a survey of recent results and methods used in the classification of torsion subgroups of elliptic curves over finite and infinite extensions of the rationals, and over function fields. Recording during the meeting "Diophantine Geometry" the May 22, 2018 at th
From playlist Math Talks
1. Introduction to Effective Field Theory (EFT)
MIT 8.851 Effective Field Theory, Spring 2013 View the complete course: http://ocw.mit.edu/8-851S13 Instructor: Iain Stewart In this lecture, the professor discussed EFT of Hydrogen, top-down and bottom-up, and renormalizable EFT. License: Creative Commons BY-NC-SA More information at ht
From playlist MIT 8.851 Effective Field Theory, Spring 2013
From playlist Abstract Algebra 2
Field Theory - Algebraically Closed Fields - Lecture 9
In this video we define what an algebraically closed field and assert without proof that they exist. We also explain why if you can find a single root for any polynomial, then you can find them all.
From playlist Field Theory