Set theory | General topology | Families of sets

Finite intersection property

In general topology, a branch of mathematics, a non-empty family A of subsets of a set is said to have the finite intersection property (FIP) if the intersection over any finite subcollection of is non-empty. It has the strong finite intersection property (SFIP) if the intersection over any finite subcollection of is infinite. Sets with the finite intersection property are also called centered systems and filter subbases. The finite intersection property can be used to reformulate topological compactness in terms of closed sets; this is its most prominent application. Other applications include proving that certain perfect sets are uncountable, and the construction of ultrafilters. (Wikipedia).

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Finite Intersection Property

In this video, I discuss the finite intersection property, which is a nice generalization of the Cantor Intersection Theorem and a very elegant application of compactness. Enjoy this topology-filled adventure! Compactness: https://youtu.be/xiWizwjpt8o Cantor Intersection Theorem: https:/

From playlist Topology

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Infinite Intersection of Open Sets that is Closed Proof

Infinite Intersection of Open Sets that is Closed Proof If you enjoyed this video please consider liking, sharing, and subscribing. You can also help support my channel by becoming a member https://www.youtube.com/channel/UCr7lmzIk63PZnBw3bezl-Mg/join Thank you:)

From playlist Topology

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Math 131 092116 Properties of Compact Sets

Properties of compact sets. Compact implies closed; closed subsets of compact sets are compact; collections of compact sets that satisfy the finite intersection property have a nonempty intersection; infinite subsets of compact sets must have a limit point; the infinite intersection of ne

From playlist Course 7: (Rudin's) Principles of Mathematical Analysis

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Math 131 Fall 2018 100118 Properties of Compact Sets

Review of compactness. Properties: compactness is not relative. Compact implies closed. Closed subset of compact set is compact. [Infinite] Collection of compact sets with finite intersection property has a nonempty intersection.

From playlist Course 7: (Rudin's) Principles of Mathematical Analysis (Fall 2018)

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Topology: Compactness

This video is about compactness and some of its basic properties.

From playlist Basics: Topology

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Math 101 Introduction to Analysis 113015: Compact Sets, ct'd

Compact sets, continued. Recalling various facts about compact sets. Compact implies infinite subsets have limit points (accumulation points), that is, compactness implies limit point compactness; collections of compact sets with the finite intersection property have nonempty intersectio

From playlist Course 6: Introduction to Analysis

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Lecture 21 (w/J. Sands!): Intersections and Unions of Indexed Families of Sets (+Arch Property)

course page: https://www.uvm.edu/~tdupuy/logic/Math52-Fall2017.html handouts - DZB, Emory videography - Eric Melton, UVM

From playlist Fundamentals of Mathematics

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Cantor Intersection Theorem

Here is a wonderful theorem about the intersection of decreasing closed sets, called the Cantor Intersection Theorem, also known as the Finite Intersection Property. Enjoy! Topology Playlist: https://www.youtube.com/playlist?list=PLJb1qAQIrmmA13vj9xkHGGBXRMV32EKVI Subscribe to my channel:

From playlist Topology

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Math 101 Fall 2017 120117 Compact Sets: The Heine-Borel Theorem

Theorem: the continuous image of a compact set is compact. Theorem: a collection of compact sets satisfying the finite intersection property has a non-empty intersection. Theorem: In R, closed and bounded intervals are compact. Corollary: Heine-Borel theorem (in R, a set is compact iff

From playlist Course 6: Introduction to Analysis (Fall 2017)

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Lecture 8: Lebesgue Measurable Subsets and Measure

MIT 18.102 Introduction to Functional Analysis, Spring 2021 Instructor: Dr. Casey Rodriguez View the complete course: https://ocw.mit.edu/courses/18-102-introduction-to-functional-analysis-spring-2021/ YouTube Playlist: https://www.youtube.com/watch?v=cqdUuREzGuo&list=PLUl4u3cNGP63micsJp_

From playlist MIT 18.102 Introduction to Functional Analysis, Spring 2021

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Stable and NIP regularity in groups - G. Conant - Workshop 1 - CEB T1 2018

Gabriel Conant (Notre Dame) / 01.02.2018 We use local stability theory to prove a group version of Szemer´edi regularity for stable subsets of finite groups. Toward generalizing this result to the NIP setting, we consider definable set systems of finite VC-dimension in pseudofinite groups

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

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Lecture 7: Sigma Algebras

MIT 18.102 Introduction to Functional Analysis, Spring 2021 Instructor: Dr. Casey Rodriguez View the complete course: https://ocw.mit.edu/courses/18-102-introduction-to-functional-analysis-spring-2021/ YouTube Playlist: https://www.youtube.com/watch?v=OHiu2F18dFA&list=PLUl4u3cNGP63micsJp_

From playlist MIT 18.102 Introduction to Functional Analysis, Spring 2021

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Parvaneh Joharinad (7/27/22): Curvature of data

Abstract: How can one determine the curvature of data and how does it help to derive the salient structural features of a data set? After determining the appropriate model to represent data, the next step is to derive the salient structural features of data based on the tools available for

From playlist Applied Geometry for Data Sciences 2022

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Plenary lecture 6 by Mladen Bestvina

Geometry Topology and Dynamics in Negative Curvature URL: https://www.icts.res.in/program/gtdnc DATES: Monday 02 Aug, 2010 - Saturday 07 Aug, 2010 VENUE : Raman Research Institute, Bangalore DESCRIPTION: This is An ICM Satellite Conference. The conference intends to bring together ma

From playlist Geometry Topology and Dynamics in Negative Curvature

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Math 131 092816 Continuity; Continuity and Compactness

Review definition of limit. Definition of continuity at a point; remark about isolated points; connection with limits. Composition of continuous functions. Alternate characterization of continuous functions (topological definition). Continuity and compactness: continuous image of a com

From playlist Course 7: (Rudin's) Principles of Mathematical Analysis

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Topological space | Lebesgue measure | Closure (topology) | Fréchet filter | Ultrafilter (set theory) | Pi-system | Intersection (set theory) | Uncountable set | Total order | Rational number | Perfect set | Sunflower (mathematics) | Empty set | Locally compact space | Hausdorff space | Filter (set theory) | Neighbourhood (mathematics) | Borel set | General topology | Mathematics | Set (mathematics) | Real number | Family of sets | Closed set | Subset | Bijection | Compact space | Tychonoff's theorem | Power set | Image (mathematics) | Open set