Ergodic theory

Kolmogorov automorphism

In mathematics, a Kolmogorov automorphism, K-automorphism, K-shift or K-system is an invertible, measure-preserving automorphism defined on a standard probability space that obeys Kolmogorov's zero–one law. All Bernoulli automorphisms are K-automorphisms (one says they have the K-property), but not vice versa. Many ergodic dynamical systems have been shown to have the K-property, although more recent research has shown that many of these are in fact Bernoulli automorphisms. Although the definition of the K-property seems reasonably general, it stands in sharp distinction to the Bernoulli automorphism. In particular, the Ornstein isomorphism theorem does not apply to K-systems, and so the entropy is not sufficient to classify such systems – there exist uncountably many non-isomorphic K-systems with the same entropy. In essence, the collection of K-systems is large, messy and uncategorized; whereas the B-automorphisms are 'completely' described by Ornstein theory. (Wikipedia).

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Homomorphisms in abstract algebra

In this video we add some more definition to our toolbox before we go any further in our study into group theory and abstract algebra. The definition at hand is the homomorphism. A homomorphism is a function that maps the elements for one group to another whilst maintaining their structu

From playlist Abstract algebra

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Group automorphisms in abstract algebra

Group automorphisms are bijective mappings of a group onto itself. In this tutorial I define group automorphisms and introduce the fact that a set of such automorphisms can exist. This set is proven to be a subgroup of the symmetric group. You can learn more about Mathematica on my Udem

From playlist Abstract algebra

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Group Isomorphisms in Abstract Algebra

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From playlist Abstract Algebra

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Isomorphisms in abstract algebra

In this video I take a look at an example of a homomorphism that is both onto and one-to-one, i.e both surjective and injection, which makes it a bijection. Such a homomorphism is termed an isomorphism. Through the example, I review the construction of Cayley's tables for integers mod 4

From playlist Abstract algebra

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Group Homomorphisms - Abstract Algebra

A group homomorphism is a function between two groups that identifies similarities between them. This essential tool in abstract algebra lets you find two groups which are identical (but may not appear to be), only similar, or completely different from one another. Homomorphisms will be

From playlist Abstract Algebra

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Introduction to additive combinatorics lecture 5.8 --- Freiman homomorphisms and isomorphisms.

The notion of a Freiman homomorphism and the closely related notion of a Freiman isomorphism are fundamental concepts in additive combinatorics. Here I explain what they are and prove a lemma that states that a subset A of F_p^N such that kA - kA is not too large is "k-isomorphic" to a sub

From playlist Introduction to Additive Combinatorics (Cambridge Part III course)

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From playlist Gregory Margulis

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From playlist Modern Algebra - Chapter 17 (group homomorphisms)

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Yakov Sinai - The Abel Prize interview 2014

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From playlist The Abel Prize Interviews

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PMSP - Random-like behavior in deterministic systems - Benjamin Weiss

Benjamin Weiss Einstein Institute of Math, Hebrew University June 16, 2010 For more videos, visit http://video.ias.edu

From playlist Mathematics

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Lewis Bowen - Classification of Bernoulli shifts

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This lecture was held at The University of Oslo, May 21, 2008 and was part of the Abel Prize Lectures in connection with the Abel Prize Week celebrations. Program for the Abel Lectures 2008 1. Abel Laureate John Thompson: “Dirichlet series and SL(2,Z)" 2. Abel Laureate Jacques Tits: “Alg

From playlist Abel Lectures

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Andreï Kolmogorov: un grand mathématicien au coeur d'un siècle tourmenté

Conférence grand public au CIRM Luminy Andreï Kolmogorov est un mathématicien russe (1903-1987) qui a apporté des contributions frappantes en théorie des probabilités, théorie ergodique, turbulence, mécanique classique, logique mathématique, topologie, théorie algorithmique de l'informati

From playlist OUTREACH - GRAND PUBLIC

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Surjective homomorphisms in abstract algebra

We have looked at homomorphisms before: https://www.youtube.com/watch?v=uTIvIFmVEAg&list=PLsu0TcgLDUiI2VH4ubaKNLxp8O5DN9pF3&index=33 https://www.youtube.com/watch?v=NuYczPkUZGY&list=PLsu0TcgLDUiI2VH4ubaKNLxp8O5DN9pF3&index=34 https://www.youtube.com/watch?v=3Oo0O1vVPoQ&list=PLsu0TcgLDUiI2V

From playlist Abstract algebra

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Isomorphisms (Abstract Algebra)

An isomorphism is a homomorphism that is also a bijection. If there is an isomorphism between two groups G and H, then they are equivalent and we say they are "isomorphic." The groups may look different from each other, but their group properties will be the same. Be sure to subscribe s

From playlist Abstract Algebra

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Randomness and Kolmogorov Complexity

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From playlist Spanning Tree's Most Recent

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Dissipation and singularities - Dubrulle - Workshop 1 - CEB T3 2019

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From playlist 2019 - T3 - The Mathematics of Climate and the Environment

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Nicola Garofalo: Hypoelliptic operators and analysis on Carnot-Carathéodory spaces

Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual Mathematics Library: http://library.cirm-math.fr. And discover all its functionalities: - Chapter markers and keywords to watch the parts of your choice in the video - Videos enriched with abstracts, b

From playlist Algebraic and Complex Geometry

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Bourbaki - 16/01/2016 - 1/4 - Damien GABORIAU

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From playlist Bourbaki - 16 janvier 2016

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Homomorphisms in abstract algebra examples

Yesterday we took a look at the definition of a homomorphism. In today's lecture I want to show you a couple of example of homomorphisms. One example gives us a group, but I take the time to prove that it is a group just to remind ourselves of the properties of a group. In this video th

From playlist Abstract algebra

Related pages

Mathematics | Dynamical system | Standard probability space | Almost everywhere | Automorphism | Kolmogorov's zero–one law | Ornstein isomorphism theorem