4-manifolds

Capped grope

In mathematics, a grope is a construction used in 4-dimensional topology, introduced by and named by "because of its multitudinous fingers". Capped gropes were used by as a substitute for Casson handles, that work better for non-simply-connected 4-manifolds. A capped surface in a 4-manifold is roughly a surface together with some 2-disks, called caps, whose boundaries generate the fundamental group of the surface. A capped grope is obtained by repeatedly replacing the caps of a capped surface by another capped surface. Capped surfaces and capped gropes are studied in . (Wikipedia).

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Vernier caliper / diameter and length of daily used objects.

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From playlist Fine Measurements

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What is the difference between convex and concave

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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What are convex polygons

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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What is the difference between convex and concave polygons

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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What is a net

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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What is a concave polygon

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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Sketch a net from a 3D figure

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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The rising sea: Grothendieck on simplicity and generality - Colin McLarty [2003]

Slides for this talk: https://drive.google.com/file/d/1yDmqhdcKo6-YpDpRdHh2hvuNirZVbcKr/view?usp=sharing Notes for this talk: https://drive.google.com/open?id=1p45B3Hh8WPRhdhQAd0Wq0MvmY0JYSnmc The History of Algebra in the Nineteenth and Twentieth Centuries April 21 - 25, 2003 Colin Mc

From playlist Mathematics

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Tropical Geometry - Lecture 4 - GrΓΆbner Bases and Tropical Bases | Bernd Sturmfels

Twelve lectures on Tropical Geometry by Bernd Sturmfels (Max Planck Institute for Mathematics in the Sciences | Leipzig, Germany) We recommend supplementing these lectures by reading the book "Introduction to Tropical Geometry" (Maclagan, Sturmfels - 2015 - American Mathematical Society)

From playlist Twelve Lectures on Tropical Geometry by Bernd Sturmfels

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Mailbag #4 - Questions About the Game Industry - Extra Credits

This week, we returned to the mailbag and answered a few more popular questions. Jump to a question via the timestamp list below: (0:22) Are you ever going to do that episode you mentioned about ____? (0:49) I'm working on a research topic similar to what you covered in an episode. Where

From playlist Extra Credits (ALL EPISODES)

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Bastiaan eats spacecake (cannabis / THC) | Drugslab

In this video Bastiaan Rosman eats spacecake to see what effect it has on his body. The spacecake Bastiaan eats contains weed (or cannabis). The principal psychoactive constituent of weed is THC or Tetrahydrocannabinol. Desired effects of THC include feeling relaxed, increased creativity,

From playlist Drug Tests

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What are the names of different types of polygons based on the number of sides

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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Alterconf Detroit 2015 - Toxic Masculinities, Sexual Violence, and Tech by Nikhil Trivedi

Toxic Masculinities, Sexual Violence, and Tech Incidences of violence in our communities over the past several decades have culminated to create hostile and unwelcoming climates for people who don’t experience the privileges of the majority. While we make concerted efforts to recruit new

From playlist AlterConf Detroit 2015

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Why Did We Test Nukes in Space?

At a time when the game of nuclear chicken very nearly got out of hand the superpowers continued to test nuclear weapons in space with both surprising and frightening consequences. In this video we look at why we needed to test nukes in space. The video that inspired this is here https://

From playlist Weapons

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Big Guns: The Muscular System - CrashCourse Biology #31

Hank tells us the story of the complicated chemical dance that allows our skeletal muscles to contract and relax. Table of Contents 1) Cardiac, Smooth, & Skeletal Muscles 01:09 2) Muscle Anatomy 02:03 a) Muscle Fibers 03:07 b) Myofibrils 04:15:1 c) Sarcomeres 04:19:1 d) Myofilaments 04:37

From playlist Biology

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Neutrino mixing and baryogenesis via leptogenesis from complex sacling by Probir Roy

Candles of Darkness DATE: 05 June TIME2017 to 09 June 2017 VENUE:Ramanujan Lecture Hall, ICTS Bangalore DARK MATTER AND THE SEARCH FOR PHYSICS BEYOND THE STANDARD MODEL "Darkness is your candle. Your boundaries are your quest."- Jalal-ud-din Rumi of Balkh (1207 - 1273) High energy Phys

From playlist Candles of Darkness

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Nonetheless one should learn the language of topos: Grothendieck... - Colin McLarty [2018]

Grothendieck's 1973 topos lectures Colin McLarty 3 mai 2018 In the summer of 1973 Grothendieck lectured on several subjects in Buffalo NY, and these lectures were recorded, including 33 hours on topos theory. The topos lectures were by far the most informal of the series, with the most si

From playlist Number Theory

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What is the difference between concave and convex polygons

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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Effective theories of dense quark matter and applications in neutron stars by Rishi Sharma

Candles of Darkness DATE :05 June TIME2017 to 09 June 2017 VENUE:Ramanujan Lecture Hall, ICTS Bangalore DARK MATTER AND THE SEARCH FOR PHYSICS BEYOND THE STANDARD MODEL "Darkness is your candle. Your boundaries are your quest."- Jalal-ud-din Rumi of Balkh (1207 - 1273) High energy Phys

From playlist Candles of Darkness

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Sketch a figure from a net

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

Related pages

Casson handle | Fundamental group | Mathematics | Simply connected space | Generating set of a group | 4-manifold