Polyhedra and Euler's formula | Algebraic Topology | NJ Wildberger

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  • čas přidán 27. 07. 2024
  • We investigate the five Platonic solids: tetrahedron, cube, octohedron, icosahedron and dodecahedron. Euler's formula relates the number of vertices, edges and faces. We give a proof using a triangulation argument and flow down a sphere.
    This is the eighth lecture in this beginner's course on Algebraic Topology, given by Assoc Prof N J Wildberger of the School of Mathematics and Statistics at UNSW.
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    Screenshot PDFs for my videos are available at the website wildegg.com. These give you a concise overview of the contents of the lectures for various Playlists: great for review, study and summary.
    My research papers can be found at my Research Gate page, at www.researchgate.net/profile/...
    My blog is at njwildberger.com/, where I will discuss lots of foundational issues, along with other things.
    Online courses will be developed at openlearning.com. The first one, already underway is Algebraic Calculus One at www.openlearning.com/courses/... Please join us for an exciting new approach to one of mathematics' most important subjects!
    If you would like to support these new initiatives for mathematics education and research, please consider becoming a Patron of this Channel at / njwildberger Your support would be much appreciated.
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    Here are all the Insights into Mathematics Playlists:
    Elementary Mathematics (K-6) Explained: / playlist
    list=PL8403C2F0C89B1333
    Year 9 Maths: • Year9Maths
    Ancient Mathematics: • Ancient Mathematics
    Wild West Banking: • Wild West Banking
    Sociology and Pure Mathematics: • Sociology and Pure Mat...
    Old Babylonian Mathematics (with Daniel Mansfield): / playlist
    list=PLIljB45xT85CdeBmQZ2QiCEnPQn5KQ6ov
    Math History: • MathHistory: A course ...
    Wild Trig: Intro to Rational Trigonometry: • WildTrig: Intro to Rat...
    MathFoundations: • Math Foundations
    Wild Linear Algebra: • Wild Linear Algebra
    Famous Math Problems: • Famous Math Problems
    Probability and Statistics: An Introduction: • Probability and Statis...
    Boole's Logic and Circuit Analysis: • Boole's Logic and Circ...
    Universal Hyperbolic Geometry: • Universal Hyperbolic G...
    Differential Geometry: • Differential Geometry
    Algebraic Topology: • Algebraic Topology
    Math Seminars: • MathSeminars
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    And here are the Wild Egg Maths Playlists:
    Triangle Centres: • ENCYCLOPEDIA OF TRIANG...
    Six: An elementary course in pure mathematics: • Six: An elementary cou...
    Algebraic Calculus One: • Algebraic Calculus One
    Algebraic Calculus Two: • Algebraic Calculus Two
    м

Komentáře • 13

  • @asimislam6194
    @asimislam6194 Před rokem +4

    All of your lectures are outstanding! Super clear and very engaging and full of interest 👌

  • @KipIngram
    @KipIngram Před 10 měsíci +2

    43:49 - That is a beautiful proof. Very "satisfying."

  • @allstargoldeneye
    @allstargoldeneye Před 12 lety +4

    what a teacher. Your filled with knowledge and wisdom.

  • @chiccocalleri
    @chiccocalleri Před 11 lety +6

    Beautiful lesson indeed !
    As i am a teacher in italian seccondary school I hope to bring something of this proof of Euler formula in my classes. Why not ?

  • @Reliquancy
    @Reliquancy Před 11 lety +2

    Wow that is a mind-blowing proof. I'd been asked whether I was related to William Thurston before but had never seen any of his ideas explained.

  • @njwildberger
    @njwildberger  Před 11 lety

    You obviously have some rare skill to make these lovely solids, thanks for letting us know.

  • @njwildberger
    @njwildberger  Před 11 lety

    A billion dollars would be way to much, I wouldn't know what to do with it. Thanks for the support, and it is a nice idea!

  • @isabelweissman388
    @isabelweissman388 Před 4 lety +1

    Super helpful!!

  • @HerbBennett
    @HerbBennett Před 2 lety

    Euler's FORMULA works for two face polygons and by cutting into the faces with two additional edges for a triangle we gat V-E+F =2 OR [3 -3 +2=2] bY CUTTING we add two edges for V-E+F =2 The cutting perpendicular from edge center to face center produces two new edges and one additional vertex following the flowing of charges. 4-5-+1=2. 1 represents the abstracted S2 plane as an imaginary singular dynamic.

  • @billytim7
    @billytim7 Před 11 lety

    i didnt know about archemedean solids. i love them

  • @karoshikun976
    @karoshikun976 Před 4 lety

    very helpful thank you sir!

  • @njwildberger
    @njwildberger  Před 11 lety +1

    I don't really have a text that follows these lectures. Perhaps I should ask one of my former students who might have taken good notes..