Homotopy theory

Postnikov system

In homotopy theory, a branch of algebraic topology, a Postnikov system (or Postnikov tower) is a way of decomposing a topological space's homotopy groups using an inverse system of topological spaces whose homotopy type at degree agrees with the truncated homotopy type of the original space . Postnikov systems were introduced by, and are named after, Mikhail Postnikov. (Wikipedia).

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Themes of Postmodern Philosophy

Another re-upload from the previous channel. This comes from a course on the history of philosophy by James Anderson a few of years back. I thought it provided a relatively decent overview. More details will be added later. More Short Videos: https://www.youtube.com/playlist?list=PLhP9EhPA

From playlist Shorter Clips & Videos - Philosophy Overdose

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The Russian Preoccupation with Historicism (Isaiah Berlin 1973)

TBA More Isaiah Berlin: https://www.youtube.com/playlist?list=PLhP9EhPApKE-z227nn_-_PKw5lGfojOcg #Philosophy #IsaiahBerlin

From playlist Social & Political Philosophy

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Gérard Laumon - On the derived Lusztig correspondence

Correction: The affiliation of Lei Fu is Tsinghua University. https://server.mcm.ac.cn/~zheng/LI/titles.html#Laumon

From playlist Conférence « Géométrie arithmétique en l’honneur de Luc Illusie » - 5 mai 2021

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Russian Capitalism After Communism | History

As the Soviet Union fell, Russia embraced capitalism. But Russia's definition of a "free market" doesn't exactly align with other parts of the globe. #HistoryChannel Subscribe for more from HISTORY: http://histv.co/SubscribeHistoryYT Read more: http://po.st/fall-of-soviet-union Find ou

From playlist Examine the Past | History

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Борис Н. Петров - Boris N. Petrov: Space Pioneer, Automatic Control Engineer(USSR)

The life of automatic control engineer Boris N. Petrov, a pioneer of the Russian space program. Борис Н. Петров Solved automatic control issues in rockets and ballistic missiles, He published many papers on control science with Vladislav Rutkovsky who narrates the story of his life. Leade

From playlist Russian Engineering

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Positive Grassmannian and polyhedral subdivisions – Alexander Postnikov – ICM2018

Combinatorics Invited Lecture 13.2 Positive Grassmannian and polyhedral subdivisions Alexander Postnikov Abstract: The nonnegative Grassmannian is a cell complex with rich geometric, algebraic, and combinatorial structures. Its study involves interesting combinatorial objects, such as po

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First examples of cluster structures on coordinate algebras, (Lecture 2) by Maitreyee Kulkarni

PROGRAM :SCHOOL ON CLUSTER ALGEBRAS ORGANIZERS :Ashish Gupta and Ashish K Srivastava DATE :08 December 2018 to 22 December 2018 VENUE :Madhava Lecture Hall, ICTS Bangalore In 2000, S. Fomin and A. Zelevinsky introduced Cluster Algebras as abstractions of a combinatoro-algebra

From playlist School on Cluster Algebras 2018

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Lauren Williams - Combinatorics of the amplituhedron

The amplituhedron is the image of the positive Grassmannian under a map in- duced by a totally positive matrix. It was introduced by Arkani-Hamed and Trnka to compute scattering amplitudes in N=4 super Yang Mills. I’ll give a gentle introduction to the amplituhedron, surveying its connecti

From playlist Combinatorics and Arithmetic for Physics: Special Days 2022

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Gravitational Waves and Theory - L. Blanchet - Workshop 1 - CEB T3 2018

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

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How Did Russian Oligarchs Get So Rich?

Subscribe to The Daily Upside! (Free Business & Finance Newsletter): https://bit.ly/38LgdGN Russian Oligarchs have become synonymous with superyachts, luxury mansions and the shady political maneuvering of post-Soviet Russia. Since the Russian invasion of Ukraine, Russian billionaires lik

From playlist Long Videos

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BGM-71 TOW Anti-Tank Missile: No Russian Tank is Safe in Ukraine

The battle for Bakhmut remains the most intense along the frontline, where new Ukrainian squads have been spotted on Humvees outfitted with Raytheon's BGM-71 TOW missiles. The TOW ( "Tube-launched, Optically tracked, Wire-guided") missile is an anti-tank missile that has become a mainstay

From playlist Military Mechanics

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What Are Phased Arrays?

This video introduces the concept of phased arrays. An array refers to multiple sensors, arranged in some configuration, that act together to produce a desired sensor pattern. With a phased array, we can electronically steer that pattern without having to physically move the array simply b

From playlist Understanding Phased Array Systems and Beamforming

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Deadly Russian Ground Forces Military Vehicles 3D

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From playlist Comparison

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First examples of cluster structures on coordinate algebras... (Lecture 3) by Maitreyee Kulkarni

PROGRAM :SCHOOL ON CLUSTER ALGEBRAS ORGANIZERS :Ashish Gupta and Ashish K Srivastava DATE :08 December 2018 to 22 December 2018 VENUE :Madhava Lecture Hall, ICTS Bangalore In 2000, S. Fomin and A. Zelevinsky introduced Cluster Algebras as abstractions of a combinatoro-algebra

From playlist School on Cluster Algebras 2018

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Martina Lanini: Totally nonnegative Grassmannians, Grassmann necklaces and quiver Grassmannians

30 September 2021 Abstract: Totally nonnegative (tnn) Grassmannians are subvarieties of (real) Grassmannians which have been widely investigated thanks to the several applications in mathematics and physics. In a seminal paper on the subject, Postnikov constructed a cellularisation of the

From playlist Representation theory's hidden motives (SMRI & Uni of Münster)

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Courtney Thatcher - Classifying $(Z/p)^2$ actions on products of spheres

38th Annual Geometric Topology Workshop (Online), June 15-17, 2021 Courtney Thatcher, University of Puget Sound Title: Classifying $(Z/p)^2$ actions on products of spheres Abstract: We consider free actions of $(Z/p)^2$ on $S^{2n-1}\times S^{2n-1}$ given by linear actions of $(Z/p)^2$ on

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First examples of cluster structures on coordinate algebras,... (Lecture 1) by Maitreyee Kulkarni

PROGRAM :SCHOOL ON CLUSTER ALGEBRAS ORGANIZERS :Ashish Gupta and Ashish K Srivastava DATE :08 December 2018 to 22 December 2018 VENUE :Madhava Lecture Hall, ICTS Bangalore In 2000, S. Fomin and A. Zelevinsky introduced Cluster Algebras as abstractions of a combinatoro-algebra

From playlist School on Cluster Algebras 2018

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Linear Desface

Here we show a quick way to set up a face in desmos using domain and range restrictions along with sliders. @shaunteaches

From playlist desmos

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Arun Debray - Stable diffeomorphism classification of some unorientable 4-manifolds

38th Annual Geometric Topology Workshop (Online), June 15-17, 2021 Arun Debray, The University of Texas at Austin Title: Stable diffeomorphism classification of some unorientable 4-manifolds Abstract: Kreck's modified surgery theory provides a bordism-theoretic classification of closed, c

From playlist 38th Annual Geometric Topology Workshop (Online), June 15-17, 2021

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Brutal Execution of the Romanovs | History

The brutal violence of the Russian Revolution culminated in the execution of Tsar Nicholas II and his entire family, ending 300 years of Romanov rule over the Russian Empire. #HistoryChannel Subscribe for more from HISTORY: http://histv.co/SubscribeHistoryYT Read More: http://po.st/romano

From playlist Examine the Past | History

Related pages

Topological space | Hurewicz theorem | Homotopy | Homotopy group | String group | Homotopy groups of spheres | Group cohomology | CW complex | Freudenthal suspension theorem | Algebraic topology | Classifying space | Obstruction theory | Homotopy theory | Pointed space | Eilenberg–MacLane space | Spectrum (topology) | Ind-completion | Spin geometry | Pushout (category theory) | Weak equivalence (homotopy theory) | Connected space | ∞-groupoid | N-sphere | Cobordism | Universal coefficient theorem | Fibration | Serre spectral sequence | Adams spectral sequence | Stable homotopy theory | Contractible space | Homotopy fiber | Simply connected space