Geometric topology | Geometric group theory | Theorems in group theory

Grushko theorem

In the mathematical subject of group theory, the Grushko theorem or the Grushko–Neumann theorem is a theorem stating that the rank (that is, the smallest cardinality of a generating set) of a free product of two groups is equal to the sum of the ranks of the two free factors. The theorem was first obtained in a 1940 article of Grushko and then, independently, in a 1943 article of Neumann. (Wikipedia).

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An introduction to the Gromov-Hausdorff distance

Title: An introduction to the Gromov-Hausdorff distance Abstract: We give a brief introduction to the Hausdorff and Gromov-Hausdorff distances between metric spaces. The Hausdorff distance is defined on two subsets of a common metric space. The Gromov-Hausdorff distance is defined on any

From playlist Tutorials

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Nicolò Zava (3/17/23): Every stable invariant of finite metric spaces produces false positives

In computational topology and geometry, the Gromov-Hausdorff distance between metric spaces provides a theoretical framework to tackle the problem of shape recognition and comparison. However, the direct computation of the Gromov-Hausdorff distance between finite metric spaces is known to

From playlist Vietoris-Rips Seminar

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Chloe Perin: Forking independence in the free group

The lecture was held within the framework of the Hausdorff Trimester Program: Logic and Algorithms in Group Theory. Abstract: Model theorists define, in structures whose first-order theory is "stable" (i.e. suitably nice), a notion of independence between elements. This notion coincides f

From playlist HIM Lectures: Trimester Program "Logic and Algorithms in Group Theory"

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Dimitri Zvonkine - On two ELSV formulas

The ELSV formula (discovered by Ekedahl, Lando, Shapiro and Vainshtein) is an equality between two numbers. The first one is a Hurwitz number that can be defined as the number of factorizations of a given permutation into transpositions. The second is the integral of a characteristic class

From playlist 4th Itzykson Colloquium - Moduli Spaces and Quantum Curves

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Mikhael Gromov - 1/6 Probability, symmetry, linearity

I plan six lectures on possible directions of modification/generalization of the probability theory, both concerning mathematical foundations and applications within and without pure mathematics. Specifically, I will address two issues. 1. Enhancement of stochastic symmetry by linearizat

From playlist Mikhael Gromov - Probability, symmetry, linearity

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Mikhail Gromov - 3/4 Old, New and Unknown around Scalar Curvature

Geometry of scalar curvature, that is comparable in scope to symplectic geometry, mediates between two worlds: the domain of rigidity, one sees in convexity and the realm of softness, characteristic of topology, such as the cobordism theory. The aim of this course is threefold: 1. An ove

From playlist Mikhail Gromov - Old, New and Unknown around Scalar Curvature

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On the Gromov width of polygon spaces - Alessia Mandini

Alessia Mandini University of Pavia October 31, 2014 After Gromov's foundational work in 1985, problems of symplectic embeddings lie in the heart of symplectic geometry. The Gromov width of a symplectic manifold (M,ω)(M,ω) is a symplectic invariant that measures, roughly speaking, the siz

From playlist Mathematics

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Mikhael Gromov - 3/6 Probability, symmetry, linearity

I plan six lectures on possible directions of modification/generalization of the probability theory, both concerning mathematical foundations and applications within and without pure mathematics. Specifically, I will address two issues. 1. Enhancement of stochastic symmetry by linearizat

From playlist Mikhael Gromov - Probability, symmetry, linearity

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Mikhail Gromov - 4/4 Old, New and Unknown around Scalar Curvature

Geometry of scalar curvature, that is comparable in scope to symplectic geometry, mediates between two worlds: the domain of rigidity, one sees in convexity and the realm of softness, characteristic of topology, such as the cobordism theory. The aim of this course is threefold: 1. An ove

From playlist Mikhail Gromov - Old, New and Unknown around Scalar Curvature

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Mikhael Gromov - 2/6 Probability, symmetry, linearity

I plan six lectures on possible directions of modification/generalization of the probability theory, both concerning mathematical foundations and applications within and without pure mathematics. Specifically, I will address two issues. 1. Enhancement of stochastic symmetry by linearizat

From playlist Mikhael Gromov - Probability, symmetry, linearity

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Calculus 1 (Stewart) Ep 22, Mean Value Theorem (Oct 28, 2021)

This is a recording of a live class for Math 1171, Calculus 1, an undergraduate course for math majors (and others) at Fairfield University, Fall 2021. The textbook is Stewart. PDF of the written notes, and a list of all episodes is at the class website. Class website: http://cstaecker.f

From playlist Math 1171 (Calculus 1) Fall 2021

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Equidistribution of Unipotent Random Walks on Homogeneous spaces by Emmanuel Breuillard

PROGRAM : ERGODIC THEORY AND DYNAMICAL SYSTEMS (HYBRID) ORGANIZERS : C. S. Aravinda (TIFR-CAM, Bengaluru), Anish Ghosh (TIFR, Mumbai) and Riddhi Shah (JNU, New Delhi) DATE : 05 December 2022 to 16 December 2022 VENUE : Ramanujan Lecture Hall and Online The programme will have an emphasis

From playlist Ergodic Theory and Dynamical Systems 2022

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What is Green's theorem? Chris Tisdell UNSW

This lecture discusses Green's theorem in the plane. Green's theorem not only gives a relationship between double integrals and line integrals, but it also gives a relationship between "curl" and "circulation". In addition, Gauss' divergence theorem in the plane is also discussed, whic

From playlist Vector Calculus @ UNSW Sydney. Dr Chris Tisdell

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Real Analysis Ep 32: The Mean Value Theorem

Episode 32 of my videos for my undergraduate Real Analysis course at Fairfield University. This is a recording of a live class. This episode is more about the mean value theorem and related ideas. Class webpage: http://cstaecker.fairfield.edu/~cstaecker/courses/2020f3371/ Chris Staecker

From playlist Math 3371 (Real analysis) Fall 2020

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Pythagorean theorem - What is it?

► My Geometry course: https://www.kristakingmath.com/geometry-course Pythagorean theorem is super important in math. You will probably learn about it for the first time in Algebra, but you will literally use it in Algebra, Geometry, Trigonometry, Precalculus, Calculus, and beyond! That’s

From playlist Geometry

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

This is a Wolfram Physics Project working session on metamathematics and its physicalization in the Wolfram Model. Begins at 10:15 Originally livestreamed at: https://twitch.tv/stephen_wolfram Stay up-to-date on this project by visiting our website: http://wolfr.am/physics Check out the

From playlist Wolfram Physics Project Livestream Archive

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Johnathan Bush (7/8/2020): Borsuk–Ulam theorems for maps into higher-dimensional codomains

Title: Borsuk–Ulam theorems for maps into higher-dimensional codomains Abstract: I will describe Borsuk-Ulam theorems for maps of spheres into higher-dimensional codomains. Given a continuous map from a sphere to Euclidean space, we say the map is odd if it respects the standard antipodal

From playlist AATRN 2020

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Worldwide Calculus: Extrema and the Mean Value Theorem

Lecture on 'Extrema and the Mean Value Theorem' from 'Worldwide Differential Calculus' and 'Worldwide AP Calculus'. For more lecture videos and $10 digital textbooks, visit www.centerofmath.org.

From playlist Worldwide Single-Variable Calculus for AP®

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Mikhail Gromov - 2/4 Old, New and Unknown around Scalar Curvature

Geometry of scalar curvature, that is comparable in scope to symplectic geometry, mediates between two worlds: the domain of rigidity, one sees in convexity and the realm of softness, characteristic of topology, such as the cobordism theory. The aim of this course is threefold: 1. An ove

From playlist Mikhail Gromov - Old, New and Unknown around Scalar Curvature

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Stokes' Theorem and Green's Theorem

Stokes' theorem is an extremely powerful result in mathematical physics. It allows us to quantify how much a vector field is circulating or rotating, based on the integral of the curl. @eigensteve on Twitter eigensteve.com databookuw.com %%% CHAPTERS %%% 0:00 Stoke's Theorem Overview

From playlist Engineering Math: Vector Calculus and Partial Differential Equations

Related pages

Homeomorphism | Groupoid | Bass–Serre theory | 3-manifold | Rank of a group | Free product | Free group | CW complex | Finitely generated group | Permutation group | Group isomorphism | Relatively hyperbolic group | Generating set of a group | Graph of groups | Finitely presented group | Connected sum | Mathematics | Group theory | Fundamental group | Group homomorphism | Cardinality | Conjugacy class