Axioms of set theory | Theorems in the foundations of mathematics

Well-ordering theorem

In mathematics, the well-ordering theorem, also known as Zermelo's theorem, states that every set can be well-ordered. A set X is well-ordered by a strict total order if every non-empty subset of X has a least element under the ordering. The well-ordering theorem together with Zorn's lemma are the most important mathematical statements that are equivalent to the axiom of choice (often called AC, see also Axiom of choice § Equivalents). Ernst Zermelo introduced the axiom of choice as an "unobjectionable logical principle" to prove the well-ordering theorem. One can conclude from the well-ordering theorem that every set is susceptible to transfinite induction, which is considered by mathematicians to be a powerful technique. One famous consequence of the theorem is the Banach–Tarski paradox. (Wikipedia).

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Well-Ordering and Induction: Part 1

This was recorded as supplemental material for Math 115AH at UCLA in the spring quarter of 2020. In this video, I prove the equivalence of the principle of mathematical induction and the well-ordering principle.

From playlist Well Ordering and Induction

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Set Theory 1.4 : Well Orders, Order Isomorphisms, and Ordinals

In this video, I introduce well ordered sets and order isomorphisms, as well as segments. I use these new ideas to prove that all well ordered sets are order isomorphic to some ordinal. Email : fematikaqna@gmail.com Discord: https://discord.gg/ePatnjV Subreddit : https://www.reddit.com/r/

From playlist Set Theory

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Discrete Math - 5.2.1 The Well-Ordering Principle and Strong Induction

In this video we introduce the well-ordering principle and look and one proof by strong induction. Textbook: Rosen, Discrete Mathematics and Its Applications, 7e Playlist: https://www.youtube.com/playlist?list=PLl-gb0E4MII28GykmtuBXNUNoej-vY5Rz

From playlist Discrete Math I (Entire Course)

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Zorn's Lemma, The Well-Ordering Theorem, and Undefinability (Version 2.0)

Zorn's Lemma and The Well-ordering Theorem are seemingly straightforward statements, but they give incredibly mind-bending results. Orderings, Hasse Diagrams, and the Ordinals / set theory will come up in this video as tools to get a better view of where the "proof" of Zorn's lemma comes f

From playlist The New CHALKboard

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14 Ordering of sets

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

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Here I have already diverted from the standard Principle as the Well-ordering Principle usually goes with the Natural Numbers (ℕ) and the Division Algorithm over the Integers (ℤ). Here's some more nice content. Well-ordering Principle: 1. https://en.wikipedia.org/wiki/Well-ordering_princi

From playlist Summer of Math Exposition 2 videos

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Well Ordering and Induction: Part 2

This was recorded as supplemental material for Math 115AH at UCLA in the spring quarter of 2020. In this video, I discuss the "philosophical importance" of induction, and go over two proofs that use the Principle of Mathematical Induction and the Well-Ordering Principle, respectively.

From playlist Well Ordering and Induction

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1.3.1 Well Ordering Principle 1: Video

MIT 6.042J Mathematics for Computer Science, Spring 2015 View the complete course: http://ocw.mit.edu/6-042JS15 Instructor: Albert R. Meyer License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu

From playlist MIT 6.042J Mathematics for Computer Science, Spring 2015

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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

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Gabriel Goldberg: The Jackson analysis and the strongest hypotheses

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From playlist Logic and Foundations

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From playlist Theory of numbers

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This is lecture 4 of an online course on mathematical group theory. It introduces Lagrange's theorem that the order of a subgroup divides the order of a group, and uses it to show that all groups of prime order are cyclic, and to prove Fermat's theorem and Euler's theorem.

From playlist Group theory

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Abstract Algebra - 7.2 LaGrange’s Theorem and Consequences

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From playlist Abstract Algebra - Entire Course

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Lagrange's Theorem and Index of Subgroups | Abstract Algebra

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From playlist Abstract Algebra

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Wolfram Physics Project: Working Session Sept. 15, 2020 [Physicalization of Metamathematics]

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From playlist Wolfram Physics Project Livestream Archive

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Visual Group Theory, Lecture 5.4: Fixed points and Cauchy's theorem

Visual Group Theory, Lecture 5.4: Fixed points and Cauchy's theorem We begin with a small lemma stating that if a group of prime order acts on a set S, then the number of fixed points is congruent to the size of the set, modulo p. We need this result to prove Cauchy's theorem, which says

From playlist Visual Group Theory

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The abstract chromatic number - Leonardo Nagami Coregliano

Computer Science/Discrete Mathematics Seminar I Topic: The abstract chromatic number Speaker: Leonardo Nagami Coregliano Affiliation: University of Chicago Date: March 22, 2021 For more video please visit http://video.ias.edu

From playlist Mathematics

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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

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15 Properties of partially ordered sets

When a relation induces a partial ordering of a set, that set has certain properties with respect to the reflexive, (anti)-symmetric, and transitive properties.

From playlist Abstract algebra

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Introduction to number theory lecture 11. Euler's theorem

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 This lecture covers Euler's generalization of Fermat's theorem. The textbook is "An introd

From playlist Introduction to number theory (Berkeley Math 115)

Related pages

Well-order | Mathematics | Transfinite induction | Set (mathematics) | Banach–Tarski paradox | Mizar system | Zorn's lemma