Order theory | Set theory | General topology

Filter (set theory)

In mathematics, a filter on a set is a family of subsets such that: 1. * and 2. * if and ,then 3. * If ,and ,then A filter on a set may be thought of as representing a "collection of large subsets". Filters appear in order, model theory, set theory, but can also be found in topology, from which they originate. The dual notion of a filter is an ideal. Filters were introduced by Henri Cartan in 1937 and as described in the article dedicated to filters in topology, they were subsequently used by Nicolas Bourbaki in their book Topologie Générale as an alternative to the related notion of a net developed in 1922 by E. H. Moore and Herman L. Smith. Order filters are generalizations of filters from sets to arbitrary partially ordered sets. Specifically, a filter on a set is just a proper order filter in the special case where the partially ordered set consists of the power set ordered by set inclusion, see the article Filter (set theory). (Wikipedia).

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Introduction to sets || Set theory Overview - Part 2

A set is the mathematical model for a collection of different things; a set contains elements or members, which can be mathematical objects of any kind: numbers, symbols, points in space, lines, other geometrical shapes, variables, or even other #sets. The #set with no element is the empty

From playlist Set Theory

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Introduction to Set Theory (Discrete Mathematics)

Introduction to Set Theory (Discrete Mathematics) This is a basic introduction to set theory starting from the very beginning. This is typically found near the beginning of a discrete mathematics course in college or at the beginning of other advanced mathematics courses. ***************

From playlist Set Theory

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Set Theory (Part 5): Functions and the Axiom of Choice

Please feel free to leave comments/questions on the video and practice problems below! In this video, I introduce functions as a special sort of relation, go over some function-related terminology, and also prove two theorems involving left- and right-inverses, with the latter theorem nic

From playlist Set Theory by Mathoma

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Set Theory (Part 2): ZFC Axioms

Please feel free to leave comments/questions on the video and practice problems below! In this video, I introduce some common axioms in set theory using the Zermelo-Fraenkel w/ choice (ZFC) system. Five out of nine ZFC axioms are covered and the remaining four will be introduced in their

From playlist Set Theory by Mathoma

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Introduction to sets || Set theory Overview - Part 1

A set is the mathematical model for a collection of different things; a set contains elements or members, which can be mathematical objects of any kind: numbers, symbols, points in space, lines, other geometrical shapes, variables, or even other #sets. The #set with no element is the empty

From playlist Set Theory

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How many functions are there?

The answer is: a lot of them! In this video, I show that F(R), the set of functions from R to R, has the same cardinality as P(R), the set of subsets of the real numbers, which, in a previous video, I’ve shown to be much bigger than R. This is set theory at its finest :)

From playlist Set theory

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What are Overlapping Sets? | Set Theory

What are overlapping sets? This is a relation between sets that I have not seen any YouTube videos on, so I figured I'd add this video explaining the term to the massive YouTube catalogue! In this video we define overlapping sets and give some examples. Two sets, A and B, are overlapping

From playlist Set Theory

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Partitions of a Set | Set Theory

What is a partition of a set? Partitions are very useful in many different areas of mathematics, so it's an important concept to understand. We'll define partitions of sets and give examples in today's lesson! A partition of a set is basically a way of splitting a set completely into disj

From playlist Set Theory

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How to Identify the Elements of a Set | Set Theory

Sets contain elements, and sometimes those elements are sets, intervals, ordered pairs or sequences, or a slew of other objects! When a set is written in roster form, its elements are separated by commas, but some elements may have commas of their own, making it a little difficult at times

From playlist Set Theory

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Gabriel Goldberg: The Jackson analysis and the strongest hypotheses

HYBRID EVENT Recorded during the meeting "XVI International Luminy Workshop in Set Theory" the September 13, 2021 by the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematician

From playlist Logic and Foundations

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Using nonstandard natural numbers in Ramsey Theory - M. Di Nasso - Workshop 1 - CEB T1 2018

Mauro Di Nasso (Pisa) / 01.02.2018 In Ramsey Theory, ultrafilters often play an instrumental role. By means of nonstandard models, one can reduce those third-order objects (ultrafilters are sets of sets of natural numbers) to simple points. In this talk we present a nonstandard technique

From playlist 2018 - T1 - Model Theory, Combinatorics and Valued fields

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Foundations S2 - Seminar 6 - Filters and ultrafilters

A seminar series on the foundations of mathematics, by Will Troiani and Billy Snikkers. In this lecture Billy introduces filters and ultrafilters and proves that a filter is maximal iff. it is an ultrafilter. The webpage for this seminar is https://metauni.org/foundations/ You can join t

From playlist Foundations seminar

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Foundations S2 - Seminar 7 - Nonstandard models of arithmetic

A seminar series on the foundations of mathematics, by Will Troiani and Billy Snikkers. In this lecture Billy uses ultrafilters to construct nonstandard models of arithmetic, the hypernaturals. Near the end is some discussion of how to read this as talking about the limits of first order l

From playlist Foundations seminar

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Ramon van Handel - Filtering in high dimension III

PROGRAM: Nonlinear filtering and data assimilation DATES: Wednesday 08 Jan, 2014 - Saturday 11 Jan, 2014 VENUE: ICTS-TIFR, IISc Campus, Bangalore LINK:http://www.icts.res.in/discussion_meeting/NFDA2014/ The applications of the framework of filtering theory to the problem of data assimi

From playlist Nonlinear filtering and data assimilation

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Discussion Meeting

PROGRAM: Nonlinear filtering and data assimilation DATES: Wednesday 08 Jan, 2014 - Saturday 11 Jan, 2014 VENUE: ICTS-TIFR, IISc Campus, Bangalore LINK:http://www.icts.res.in/discussion_meeting/NFDA2014/ The applications of the framework of filtering theory to the problem of data assimi

From playlist Nonlinear filtering and data assimilation

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A new basis theorem for ∑13 sets

Distinguished Visitor Lecture Series A new basis theorem for ∑13 sets W. Hugh Woodin Harvard University, USA and University of California, Berkeley, USA

From playlist Distinguished Visitors Lecture Series

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AMMI 2022 Course "Geometric Deep Learning" - Seminar 3 (Equivariance in ML) - Geordie Williamson

Video recording of the course "Geometric Deep Learning" taught in the African Master in Machine Intelligence in July 2022 Seminar 3 - Equivariance in Machine Learning - Geordie Williamson (U Sydney) Slides: https://www.dropbox.com/s/w10mfq072zkhsap/AIMS%202022%20-%20Seminar%203%20-%20Eq

From playlist AMMI Geometric Deep Learning Course - Second Edition (2022)

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Large deviations theory applied to large scale (...) - P. Reimberg - Workshop 1 - CEB T3 2018

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From playlist 2018 - T3 - Analytics, Inference, and Computation in Cosmology

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Every Set is an Element of its Power Set | Set Theory

Every set is an element of its own power set. This is because the power set of a set S, P(S), contains all subsets of S. By definition, every set is a subset of itself, and thus by definition of the power set of S, it must contain S. This is even true for the always-fun empty set! We discu

From playlist Set Theory

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Jamie Gabe: A new approach to classifying nuclear C*-algebras

Talk in the global noncommutative geometry seminar (Europe), 9 February 2022

From playlist Global Noncommutative Geometry Seminar (Europe)

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Hahn–Banach theorem | Lebesgue measure | Power set | Set theory | Functional analysis | Subnet (mathematics) | Symmetric relation | Ring of sets | Partially ordered set | Fréchet filter | Subsequence | Topology | Ultrafilter (set theory) | Net (mathematics) | Pi-system | Ideal (set theory) | Zorn's lemma | Upper and lower bounds | Base (topology) | Comparison of topologies | Model theory | Pointed set | Baire space | Directed set | Hausdorff space | Zermelo–Fraenkel set theory | Alfred Tarski | Binary relation | Cofiniteness | Filter (mathematics) | Transitive relation | Equivalence class | Preorder | Natural number | Henri Cartan | Mathematics | Reflexive relation | Unit (ring theory) | Surjective function | Filters in topology | Family of sets | Meagre set | Lexicographic order | E. H. Moore | Subset | Maximal and minimal elements | Greatest element and least element | Order theory | Product topology | Tychonoff's theorem | Prime number | Dense order | Cofinal (mathematics) | Equivalence relation | Nicolas Bourbaki | Antisymmetric relation | Albert Wilansky | Neighbourhood system | Serial relation | Image (mathematics) | Finite intersection property