Homotopy theory | Algebraic topology

Connective spectrum

In algebraic topology, a branch of mathematics, a connective spectrum is a spectrum whose homotopy sets of negative degrees are zero. (Wikipedia).

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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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Adding Connections on LinkedIn

In this video, you’ll learn how to add connections on LinkedIn. Visit https://edu.gcfglobal.org/en/linkedin/adding-connections-on-linkedin/1/ for our text-based lesson. We hope you enjoy!

From playlist LinkedIn

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the Internet (part 2)

An intro to the core protocols of the Internet, including IPv4, TCP, UDP, and HTTP. Part of a larger series teaching programming. See codeschool.org

From playlist The Internet

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Spectrum of Hg Lamp / amazing science experiment

Identify the spectral lines of Hg lamp Enjoy the amazing colors! Music: https://www.bensound.com/

From playlist Optics

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What are Connected Graphs? | Graph Theory

What is a connected graph in graph theory? That is the subject of today's math lesson! A connected graph is a graph in which every pair of vertices is connected, which means there exists a path in the graph with those vertices as endpoints. We can think of it this way: if, by traveling acr

From playlist Graph Theory

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Stable Homotopy Seminar, 16: The Whitehead, Hurewicz, Universal Coefficient, and Künneth Theorems

These are some generalizations of facts from unstable algebraic topology that are useful for calculating in the category of spectra. The Whitehead and Hurewicz theorems say that a map of connective spectra that's a homology isomorphism is a weak equivalence, and that the lowest nonzero hom

From playlist Stable Homotopy Seminar

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Higher Algebra 8: Spectra

In this video, we introduce and discuss spectra (in the sense of homotopy theory). We explain how they generalise abelian groups. Feel free to post comments and questions at our public forum at https://www.uni-muenster.de/TopologyQA/index.php?qa=tc-lecture Homepage with further informa

From playlist Higher Algebra

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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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Stable Homotopy Seminar, 15: Dualizable and invertible spectra

I present the useful fact that spectra are generated by finite complexes under filtered homotopy colimits. I then define Spanier-Whitehead duality, which is a special case of a notion of duality that exists in any closed symmetric monoidal category. Two natural classes of spectra rise from

From playlist Stable Homotopy Seminar

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Schemes 14: Irreducible, reduced, integral, connected

This lecture is part of an online algebraic geometry course on schemes, based on chapter II of "Algebraic geometry" by Hartshorne. We discuss the 4 properties of schemes: reduced, irreducible, integral, and connected.

From playlist Algebraic geometry II: Schemes

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Lecture 14: The Definition of TC

In this video, we finally give the definition of topological cyclic homology. In fact, we will give two definitions: the first is abstract in terms of a mapping spectrum spectrum in cyclotomic spectra and then we unfold this to a concrete definition on terms of negative topological cyclic

From playlist Topological Cyclic Homology

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Chem 125. Advanced Organic Chemistry. 28. 13C NMR Spectroscopy. Introduction to 2D NMR. COSY & HMQC.

UCI Chem 125 Advanced Organic Chemistry (Spring 2016) Chem 125. Advanced Organic Chemistry. 28. 13C NMR Spectroscopy. Introduction to 2D NMR. COSY & HMQC. View the complete course: http://ocw.uci.edu/courses/chem_125_advanced_organic_chemistry.html Instructor: James S. Nowick, Ph.D. L

From playlist Chem125: Advanced Organic Chemistry

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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 für Materialien und Energie, Germany), Yogesh Singh (IISER Mohali, In

From playlist FRUSTRATED METALS AND INSULATORS (HYBRID, 2022)

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Stéphane Nonennmacher - From Fractal Weyl Laws to spectral questions on sparse directed graphs

https://indico.math.cnrs.fr/event/3475/attachments/2180/2563/Nonnenmacher_GomaxSlides.pdf

From playlist Google matrix: fundamentals, applications and beyond

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

The fibrant spectra are the Ω-spectra, and we can give an elegant explicit description of the fibrant replacement. The "infinite loop space" functor, which is the derived right adjoint to the suspension spectrum, is then given by taking the 0th space of an equivalent Ω-spectrum. This allow

From playlist Stable Homotopy Seminar

Related pages

Mathematics | Homotopy | Spectrum (topology) | Algebraic topology