Homotopy theory

Spectrum (topology)

In algebraic topology, a branch of mathematics, a spectrum is an object representing a generalized cohomology theory. Every such cohomology theory is representable, as follows from Brown's representability theorem. This means that, given a cohomology theory , there exist spaces such that evaluating the cohomology theory in degree on a space is equivalent to computing the homotopy classes of maps to the space , that is . Note there are several different categories of spectra leading to many technical difficulties, but they all determine the same homotopy category, known as the stable homotopy category. This is one of the key points for introducing spectra because they form a natural home for stable homotopy theory. (Wikipedia).

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Topology (What is a Topology?)

What is a Topology? Here is an introduction to one of the main areas in mathematics - Topology. #topology Some of the links below are affiliate links. As an Amazon Associate I earn from qualifying purchases. If you purchase through these links, it won't cost you any additional cash, b

From playlist Topology

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What is a closed set ?

I define closed sets, an important notion in topology and analysis. It is defined in terms of limit points, and has a priori nothing to do with open sets. Yet I show the important result that a set is closed if and only if its complement is open. More topology videos can be found on my pla

From playlist Topology

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What Is Network Topology? | Types of Network Topology | BUS, RING, STAR, TREE, MESH | Simplilearn

In this video on Network Topology, we will understand What is Network topology, the role of using topology while designing a network, Different types of Topologies in a Network. Network topology provides us with a way to configure the most optimum network design according to our requiremen

From playlist Cyber Security Playlist [2023 Updated]🔥

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Continuity in Topology

In this video, I cover the notion of continuity, as used in topology. The beautiful thing is that this doesn't use epsilon-delta at all, and instead just something purely geometric. Enjoy this topology-adventure! Topology Playlist: https://youtube.com/playlist?list=PLJb1qAQIrmmA13vj9xkHGG

From playlist Topology

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Topology 1.3 : Basis for a Topology

In this video, I define what a basis for a topology is. Email : fematikaqna@gmail.com Code : https://github.com/Fematika/Animations Notes : None yet

From playlist Topology

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Topology 1.1 : Open Sets of Reals

In this video, I give a definition of the open sets on the real numbers. Email : fematikaqna@gmail.com Code : https://github.com/Fematika/Animations Notes : None yet

From playlist Topology

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Connectedness

In this video, I define connectedness, which is a very important concept in topology and math in general. Essentially, it means that your space only consists of one piece, whereas disconnected spaces have two or more pieces. I also define the related notion of path-connectedness. Topology

From playlist Topology

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Teach Astronomy - Topology of the Universe

http://www.teachastronomy.com/ Astronomers sometimes talk about the topology of the universe which is a mathematical description of the three dimensional structure in terms of mathematical shapes. Using this formalism astronomers are of course simplifying something that's actually very co

From playlist 20. Galaxy Interaction and Motion

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Teena Gerhardt - 2/3 Algebraic K-theory and Trace Methods

Algebraic K-theory is an invariant of rings and ring spectra which illustrates a fascinating interplay between algebra and topology. Defined using topological tools, this invariant has important applications to algebraic geometry, number theory, and geometric topology. One fruitful approac

From playlist Summer School 2020: Motivic, Equivariant and Non-commutative Homotopy Theory

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Teena Gerhardt - 3/3 Algebraic K-theory and Trace Methods

Algebraic K-theory is an invariant of rings and ring spectra which illustrates a fascinating interplay between algebra and topology. Defined using topological tools, this invariant has important applications to algebraic geometry, number theory, and geometric topology. One fruitful approac

From playlist Summer School 2020: Motivic, Equivariant and Non-commutative Homotopy Theory

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Commutative algebra 13 (Topology of Spec R)

This lecture is part of an online course on commutative algebra, following the book "Commutative algebra with a view toward algebraic geometry" by David Eisenbud. In this lecture we discuss the topology of the spectrum Spec R of a ring, showing that it is compact, sometimes connected, an

From playlist Commutative algebra

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Topology 1.7 : More Examples of Topologies

In this video, I introduce important examples of topologies I didn't get the chance to get to. This includes The discrete and trivial topologies, subspace topology, the lower-bound and K topologies on the reals, the dictionary order, and the line with two origins. I also introduce (again)

From playlist Topology

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Geometric Representation of Structured Extensions in Ergodic Theory - Henrik Kreidler

Special Year Research Seminar Topic: Geometric Representation of Structured Extensions in Ergodic Theory Speaker: Henrik Kreidler Affiliation: Bergische Universität Wuppertal Date: March 14, 2023 The Mackey-Zimmer representation theorem is a key structural result from ergodic theory: Eve

From playlist Mathematics

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MagLab Theory Winter School 2018: Duncan Haldane - Bipartite Entanglement I

The National MagLab held it's sixth Theory Winter School in Tallahassee, FL from January 8th - 13th, 2018.

From playlist 2018 Theory Winter School

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Commutative algebra 11 (Spectrum of a ring)

This lecture is part of an online course on commutative algebra, following the book "Commutative algebra with a view toward algebraic geometry" by David Eisenbud. In this lecture we define the spectrum of a ring as the space of prime ideals, and give a few examples. Reading: Lectures 9

From playlist Commutative algebra

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Schemes 5: Definition of a scheme

This lecture is part of an online algebraic geometry course on schemes, based on chapter II of "Algebraic geometry" by Hartshorne. We give some historical background, then give the definition of a scheme and some simple examples, and finish by explaining the origin of the word "spectrum".

From playlist Algebraic geometry II: Schemes

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Supersymmetry on the lattice: Geometry, Topology, and Spin Liquids by Simon Trebst

PROGRAM FRUSTRATED METALS AND INSULATORS (HYBRID) ORGANIZERS Federico Becca (University of Trieste, Italy), Subhro Bhattacharjee (ICTS-TIFR, India), Yasir Iqbal (IIT Madras, India), Bella Lake (Helmholtz-Zentrum Berlin fĂĽr Materialien und Energie, Germany), Yogesh Singh (IISER Mohali, In

From playlist FRUSTRATED METALS AND INSULATORS (HYBRID, 2022)

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Hermann Schulz-Baldes: Computational K-theory via the spectral localizer.

Talk by Hermann Schulz-Baldes in Global Noncommutative Geometry Seminar (Europe) http://www.noncommutativegeometry.nl/ncgseminar/ on March 24, 2021

From playlist Global Noncommutative Geometry Seminar (Europe)

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Rings 6 Prime and maximal ideals

This lecture is part of an online course on rings and modules. We discuss prime and maximal ideals of a (commutative) ring, use them to construct the spectrum of a ring, and give a few examples. For the other lectures in the course see https://www.youtube.com/playlist?list=PL8yHsr3EFj5

From playlist Rings and modules

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Definition of a Topological Space

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Definition of a Topological Space

From playlist Topology

Related pages

List of cohomology theories | Michael Atiyah | Abelian group | Connective spectrum | Unitary group | Brown's representability theorem | Symmetric spectrum | Edwin Spanier | Algebraic topology | CW complex | Freudenthal suspension theorem | Suspension (topology) | Cohomology | Sphere spectrum | Classifying space | Homotopy category | Topological Hochschild homology | Derived algebraic geometry | Eilenberg–MacLane space | Ring spectrum | Module spectrum | K-theory spectrum | Derived tensor product | Mapping spectrum | G-spectrum | Mapping cone (topology) | Mathematics | Smash product | Triangulated category | Representable functor | Category (mathematics) | Monoidal category | Spectral geometry | Adams spectral sequence | Frank Adams | Grothendieck group | Monoid | Topological K-theory