Theorems in differential topology

Hopf theorem

The Hopf theorem (named after Heinz Hopf) is a statement in differential topology, saying that the topological degree is the only homotopy invariant of continuous maps to spheres. (Wikipedia).

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What is the Hopf Fibration?

In this video I shed some light on a heavily alluded to and poorly explained object, the Hopf Fibration. The Hopf Fibration commonly shows up in discussions surrounding gauge theories and fundamental physics, though its construction is not so mysterious.

From playlist Summer of Math Exposition Youtube Videos

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Ralph Kaufmann: Graph Hopf algebras and their framework

The lecture was held within the framework of the Hausdorff Trimester Program: Periods in Number Theory, Algebraic Geometry and Physics. Abstract: I will discuss recent results linking the Hopf algebras of Goncharov for multiple zetas, the Hopf algebra of Connes and Kreimer for renormalis

From playlist Workshop: "Amplitudes and Periods"

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The Hopf-Rinow Theorem

We present a proof of the Hopf-Rinow theorem. For more details see do Carmo's "Riemannian geometry" Chapter 7.

From playlist Differential geometry

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Hopf Fibration 1

This shows a 3d print of a mathematical sculpture I produced using shapeways.com. This model is available at http://shpws.me/1mUo

From playlist 3D printing

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Berge's lemma, an animated proof

Berge's lemma is a mathematical theorem in graph theory which states that a matching in a graph is of maximum cardinality if and only if it has no augmenting paths. But what do those terms even mean? And how do we prove Berge's lemma to be true? == CORRECTION: at 7:50, the red text should

From playlist Summer of Math Exposition Youtube Videos

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Theory of numbers: Congruences: Euler's theorem

This lecture is part of an online undergraduate course on the theory of numbers. We prove Euler's theorem, a generalization of Fermat's theorem to non-prime moduli, by using Lagrange's theorem and group theory. As an application of Fermat's theorem we show there are infinitely many prim

From playlist Theory of numbers

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Walter Van SUIJLEKOM - Renormalization Hopf Algebras and Gauge Theories

We give an overview of the Hopf algebraic approach to renormalization, with a focus on gauge theories. We illustrate this with Kreimer's gauge theory theorem from 2006 and sketch a proof. It relates Hopf ideals generated by Slavnov-Taylor identities to the Hochschild cocycles that are give

From playlist Algebraic Structures in Perturbative Quantum Field Theory: a conference in honour of Dirk Kreimer's 60th birthday

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Matt SZCZESNY - Toric Hall Algebras and infinite-dimentional Lie algebras

The process of counting extensions in categories yields an associative (and sometimes Hopf) algebra called a Hall algebra. Applied to the category of Feynman graphs, this process recovers the Connes-Kreimer Hopf algebra. Other examples abound, yielding various combinatorial Hopf algebras.

From playlist Algebraic Structures in Perturbative Quantum Field Theory: a conference in honour of Dirk Kreimer's 60th birthday

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Hopf link bagel

A bagel cut into a Hopf link.

From playlist Algebraic Topology

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Homotopical effects of k-dilation - Larry Guth

Variational Methods in Geometry Seminar Topic: Homotopical effects of k-dilation Speaker: Larry Guth Affiliation: Massachusetts Institute of Technology Date: November 27, 2018 For more video please visit http://video.ias.edu

From playlist Variational Methods in Geometry

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MAE5790-12 Bifurcations in two dimensional systems

Bifurcations of fixed points: saddle-node, transcritical, pitchfork. Hopf bifurcations. Other bifurcations of periodic orbits. Reading: Strogatz, "Nonlinear Dynamics and Chaos", Sections 8.0--8.2.

From playlist Nonlinear Dynamics and Chaos - Steven Strogatz, Cornell University

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Inernal Languages for Higher Toposes - Michael Shulman

Michael Shulman University of California, San Diego; Member, School of Mathematics October 3, 2012 For more videos, visit http://video.ias.edu

From playlist Mathematics

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Cylindrical contact homology as a well-defined homology? - Joanna Nelson

Joanna Nelson University of Wisconsin-Madison September 30, 2013 For more videos, visit http://video.ias.edu

From playlist Mathematics

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Mathematical Biology. 21: Hopf Bifurcations

UCI Math 113B: Intro to Mathematical Modeling in Biology (Fall 2014) Lec 21. Intro to Mathematical Modeling in Biology: Hopf Bifurcations View the complete course: http://ocw.uci.edu/courses/math_113b_intro_to_mathematical_modeling_in_biology.html Instructor: German A. Enciso, Ph.D. Text

From playlist Math 113B: Mathematical Biology

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Bifurcation and Catastrophy theory: Physical and Natural systems by Petri Piiroinen

Modern Finance and Macroeconomics: A Multidisciplinary Approach URL: http://www.icts.res.in/program/memf2015 DESCRIPTION: The financial meltdown of 2008 in the US stock markets and the subsequent protracted recession in the Western economies have accentuated the need to understand the dy

From playlist Modern Finance and Macroeconomics: A Multidisciplinary Approach

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The second most beautiful equation and its surprising applications

Get free access to over 2500 documentaries on CuriosityStream: https://curiositystream.com/majorprep (use promo code "majorprep" at sign up) STEMerch Store: https://stemerch.com/ Support the Channel: https://www.patreon.com/zachstar PayPal(one time donation): https://www.paypal.me/ZachStar

From playlist Applied Math

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Claudia Pinzari: "Weak quasi-Hopf algebras associated to Verlinde fusion categories"

Actions of Tensor Categories on C*-algebras 2021 "Weak quasi-Hopf algebras associated to Verlinde fusion categories" Claudia Pinzari - Sapienza Università di Roma Abstract: Unitary modular fusion categories arise in various frameworks. After a general overview on unitarity, we discuss th

From playlist Actions of Tensor Categories on C*-algebras 2021

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Michael Atiyah, Seminars Geometry and Topology 1/2 [2009]

Seminars on The Geometry and Topology of the Freudenthal Magic Square Date: 9/10/2009 Video taken from: http://video.ust.hk/Watch.aspx?Video=98D80943627E7107

From playlist Mathematics

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Paul Shafer:Reverse mathematics of Caristi's fixed point theorem and Ekeland's variational principle

The lecture was held within the framework of the Hausdorff Trimester Program: Types, Sets and Constructions. Abstract: Caristi's fixed point theorem is a fixed point theorem for functions that are controlled by continuous functions but are necessarily continuous themselves. Let a 'Caristi

From playlist Workshop: "Proofs and Computation"

Related pages

Manifold | Connected space | Heinz Hopf | Degree of a continuous mapping | N-sphere | Closed manifold | Differential topology