Lemmas in group theory

Schreier's lemma

In mathematics, Schreier's lemma is a theorem in group theory used in the Schreier–Sims algorithm and also for finding a presentation of a subgroup. (Wikipedia).

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Irreducibility and the Schoenemann-Eisenstein criterion | Famous Math Probs 20b | N J Wildberger

In the context of defining and computing the cyclotomic polynumbers (or polynomials), we consider irreducibility. Gauss's lemma connects irreducibility over the integers to irreducibility over the rational numbers. Then we describe T. Schoenemann's irreducibility criterion, which uses some

From playlist Famous Math Problems

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Proof of Lemma and Lagrange's Theorem

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Proof of Lemma and Lagrange's Theorem. This video starts by proving that any two right cosets have the same cardinality. Then we prove Lagrange's Theorem which says that if H is a subgroup of a finite group G then the order of H div

From playlist Abstract Algebra

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Berge's lemma, an animated proof

Berge's lemma is a mathematical theorem in graph theory which states that a matching in a graph is of maximum cardinality if and only if it has no augmenting paths. But what do those terms even mean? And how do we prove Berge's lemma to be true? == CORRECTION: at 7:50, the red text should

From playlist Summer of Math Exposition Youtube Videos

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Burnside's Lemma (Part 2) - combining math, science and music

Part 1 (previous video): https://youtu.be/6kfbotHL0fs Orbit-stabilizer theorem: https://youtu.be/BfgMdi0OkPU Burnside's lemma is an interesting result in group theory that helps us count things with symmetries considered, e.g. in some situations, we don't want to count things that can be

From playlist Traditional topics, explained in a new way

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RIngs 22 Hensel's lemma

This lecture is part of an online course on rings and modules. We continue the previous lecture on complete rings by discussing Hensel's lemma for finding roots of polynomials over p-adic rings or over power series rings. We sketch two proofs, by slowly improving a root one digit at a tim

From playlist Rings and modules

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FIT3.1.4. Factoring Example: Artin-Schreier Polynomials

Field Theory: We show that g(x)=x^5-x+1 is irreducible over the rationals using techniques from finite fields. This leads to the definition of an Artin-Schreier polynomial, and in turn we obtain a class of irreducible polynomials over the rationals and prime characteristic.

From playlist Abstract Algebra

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A09 The Hamiltonian

Moving on from Lagrange's equation, I show you how to derive Hamilton's equation.

From playlist Physics ONE

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GAP - 2 by Alexander Hulpke

DATE & TIME 05 November 2016 to 14 November 2016 VENUE Ramanujan Lecture Hall, ICTS Bangalore Computational techniques are of great help in dealing with substantial, otherwise intractable examples, possibly leading to further structural insights and the detection of patterns in many abstra

From playlist Group Theory and Computational Methods

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Alexander HULPKE - Computational group theory, cohomology of groups and topological methods 1

The lecture series will give an introduction to the computer algebra system GAP, focussing on calculations involving cohomology. We will describe the mathematics underlying the algorithms, and how to use them within GAP. Alexander Hulpke's lectures will being with some general computation

From playlist École d'Été 2022 - Cohomology Geometry and Explicit Number Theory

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Galois theory: Artin Schreier extensions

This lecture is part of an online graduate course on Galois theory. We describe the Galois extensions with Galois group cyclic of order p, where p is the characteristic of the field. We show that these are generated by the roots of Artin-Schreier polynomials. Minor correction: Srikanth

From playlist Galois theory

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Lyapunov Stability via Sperner's Lemma

We go on whistle stop tour of one of the most fundamental tools from control theory: the Lyapunov function. But with a twist from combinatorics and topology. For more on Sperner's Lemma, including a simple derivation, please see the following wonderful video, which was my main source of i

From playlist Summer of Math Exposition Youtube Videos

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How Small Can a Group or a Graph be to Admit a Non-Trivial Poisson Boundary? - Anna Erschler

Group Theory/Dynamics Talk Topic: How Small Can a Group or a Graph be to Admit a Non-Trivial Poisson Boundary? Speaker: Anna Erschler Affiliation: École normale supérieure Date: December 9, 2022 We review results about random walks on groups, discussing results and conjectures relating c

From playlist Mathematics

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Theory of numbers: Gauss's lemma

This lecture is part of an online undergraduate course on the theory of numbers. We describe Gauss's lemma which gives a useful criterion for whether a number n is a quadratic residue of a prime p. We work it out explicitly for n = -1, 2 and 3, and as an application prove some cases of Di

From playlist Theory of numbers

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The dynamics of Aut(Fn) actions on group presentations and representations - Alexander Lubotzky

Character Varieties, Dynamics and Arithmetic Topic: The dynamics of Aut(Fn) actions on group presentations and representations Speaker: Alexander Lubotzky Affiliation: Hebrew University of Jerusalem; Visiting Professor, School of Mathematics Date: December 15, 2021 Several different area

From playlist Mathematics

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Building Expanders in Three Steps - Amir Yehudayoff

Amir Yehudayoff Technion-Israel; Institute for Advanced Study February 23, 2012 The talk will have 2 parts (between the parts we will have a break). In the first part, we will discuss two options for using groups to construct expander graphs (Cayley graphs and Schreier diagrams). Specifica

From playlist Mathematics

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Galois theory for Schrier graphs: bounded automata by Hemant Bhate

PROGRAM DYNAMICS OF COMPLEX SYSTEMS 2018 ORGANIZERS Amit Apte, Soumitro Banerjee, Pranay Goel, Partha Guha, Neelima Gupte, Govindan Rangarajan and Somdatta Sinha DATE: 16 June 2018 to 30 June 2018 VENUE: Ramanujan hall for Summer School held from 16 - 25 June, 2018; Madhava hall for W

From playlist Dynamics of Complex systems 2018

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Proof & Explanation: Gauss's Lemma in Number Theory

Euler's criterion: https://youtu.be/2IBPOI43jek One common proof of quadratic reciprocity uses Gauss's lemma. To understand Gauss's lemma, here we prove how it works using Euler's criterion and the Legendre symbol. Quadratic Residues playlist: https://www.youtube.com/playlist?list=PLug5Z

From playlist Quadratic Residues

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Steven Galbraith, Isogeny graphs, computational problems, and applications to cryptography

VaNTAGe Seminar, September 20, 2022 License: CC-BY-NC-SA Some of the papers mentioned in this talk: Ducas, Pierrot 2019: https://link.springer.com/article/10.1007/s10623-018- 0573-3 (https://rdcu.be/cVYrC) Kohel 1996: http://iml.univ-mrs.fr/~kohel/pub/thesis.pdf Fouquet, Morain 2002: ht

From playlist New developments in isogeny-based cryptography

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Henry Adams (8/30/21): Vietoris-Rips complexes of hypercube graphs

Questions about Vietoris-Rips complexes of hypercube graphs arise naturally from problems in genetic recombination, and also from Kunneth formulas for persistent homology with the sum metric. We describe the homotopy types of Vietoris-Rips complexes of hypercube graphs at small scale param

From playlist Beyond TDA - Persistent functions and its applications in data sciences, 2021

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Riemann-Lebesgue Lemma

In this video, I prove the famous Riemann-Lebesgue lemma, which states that the Fourier transform of an integrable function must go to 0 as |z| goes to infinity. This is one of the results where the proof is more important than the theorem, because it's a very classical Lebesgue integral

From playlist Real Analysis

Related pages

Transversal (combinatorics) | Schreier–Sims algorithm | Subgroup | Symmetric group | Theorem | Cayley's theorem | Section (fiber bundle) | Group theory | Presentation of a group