Order theory

Cofinal (mathematics)

In mathematics, a subset of a preordered set is said to be cofinal or frequent in if for every it is possible to find an element in that is "larger than " (explicitly, "larger than " means ). Cofinal subsets are very important in the theory of directed sets and nets, where “cofinal subnet” is the appropriate generalization of "subsequence". They are also important in order theory, including the theory of cardinal numbers, where the minimum possible cardinality of a cofinal subset of is referred to as the cofinality of (Wikipedia).

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Stable Homotopy Seminar, 3: The homotopy category of spectra

We discuss the Brown representability theorem, and give the Boardman-Vogt definition of the homotopy category of spectra. Examples include suspension spectra, Omega-spectra arising from cohomology theories, and Thom spectra. ~~~~~~~~~~~~~~~~======================~~~~~~~~~~~~~~~ This is

From playlist Stable Homotopy Seminar

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Paul GUNNELLS - Cohomology of arithmetic groups and number theory: geometric, ... 1

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

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Benjamini-Schramm Limits of Finite Volume Manifolds (Lecture-4) by Ian Biringer

PROGRAM: PROBABILISTIC METHODS IN NEGATIVE CURVATURE (ONLINE) ORGANIZERS: Riddhipratim Basu (ICTS - TIFR, Bengaluru), Anish Ghosh (TIFR, Mumbai) and Mahan M J (TIFR, Mumbai) DATE & TIME: 01 March 2021 to 12 March 2021 VENUE: Online Due to the ongoing COVID pandemic, the meeting will

From playlist Probabilistic Methods in Negative Curvature (Online)

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(Fundamental Group of an Elliptic Curve) = (Tate Module)

Here we talk about how the abelianization of the geometric algebraic fundmental group is really the Tate module.

From playlist Fundamental Groups

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Teach Astronomy - Cosmology

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From playlist 22. The Big Bang, Inflation, and General Cosmology

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Paul GUNNELLS - Cohomology of arithmetic groups and number theory: geometric, ... 2

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

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Stable Homotopy Seminar, 9: Infinite Loop Spaces, and Homotopy Colimits

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From playlist Stable Homotopy Seminar

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Stable Homotopy Seminar, 8: The Stable Model Category of Spectra

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From playlist Stable Homotopy Seminar

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Aurel PAGE - Cohomology of arithmetic groups and number theory: geometric, ... 2

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From playlist École d'Été 2022 - Cohomology Geometry and Explicit Number 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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Minerva Lectures 2012 - Ian Agol Talk 2: The virtual Haken conjecture & geometric group theory

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From playlist Minerva Lectures - Ian Agol

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Étale cohomology 9/15/2020

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From playlist Étale cohomology and the Weil conjectures

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Paul GUNNELLS - Cohomology of arithmetic groups and number theory: geometric, ... 5

In this lecture series, the first part will be dedicated to cohomology of arithmetic groups of lower ranks (e.g., Bianchi groups), their associated geometric models (mainly from hyperbolic geometry) and connexion to number theory. The second part will deal with higher rank groups, mainly

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

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Philippe ELBAZ - Cohomology of arithmetic groups and number theory: geometric, ... 3

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

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Aurel PAGE - Cohomology of arithmetic groups and number theory: geometric, ... 1

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

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Philippe ELBAZ - Cohomology of arithmetic groups and number theory: geometric, ... 2

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

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Haluk SENGUN - Cohomology of arithmetic groups and number theory: geometric, ... 2

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

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ICM 2006 Round Table

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From playlist Number Theory

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Philippe ELBAZ - Cohomology of arithmetic groups and number theory: geometric, ... 4

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

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On theories in mathematics education and their conceptual differences – Luis Radford – ICM2018

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From playlist Mathematics Education and Popularization of Mathematics

Related pages

Topological space | Inverse limit | Subnet (mathematics) | Subsequence | Partially ordered set | Net (mathematics) | Order topology | Index of a subgroup | Group (mathematics) | Duality (order theory) | Directed set | Forcing (mathematics) | Transitive relation | Dense set | Natural number | Mathematics | Reflexive relation | Function (mathematics) | Integer | Normal subgroup | Subset | Order theory | Cardinality | Profinite group | Power set | Cofinality