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Interactive video lesson plan for: Who (else) cares about topology? Stolen necklaces and Borsuk-Ulam

Activity overview:

The Borsuk-Ulam theorem from topology solving a counting puzzle. Truly unexpected, truly beautiful.
The Great Courses Plus free trial: http://ow.ly/GtbB3083BZc

Shirts/posters at DFTBA: http://3b1b.co/store

Mathologer's related video: https://youtu.be/7s-YM-kcKME
(Seriously, Mathologer is great)

VSauce on fixed points: https://youtu.be/csInNn6pfT4

The original 1986 by Alon and West with this proof: https://goo.gl/XeI58w
EE Paper using ideas related to this puzzle: https://goo.gl/bPQQpE
I first came across this paper thanks to Alon Amit's answer on this Quora post: https://goo.gl/YzFtjf

Music by Vince Rubinetti: https://soundcloud.com/vincerubinetti/riemann-zeta-function

Special thanks to the following Patrons: http://3b1b.co/borsuk-thanks

Apologies for the typos at 3:20 and 17:18. Turns out I was too engrossed with the math to think about spelling!

(As a note, for The Great Courses Plus trial, it is currently available to watch through a web browser to almost anyone in the world and optimized for the US market. The Great Courses Plus is currently working to both optimize the product globally and accept credit card payments globally)

3blue1brown is a channel about animating math, in all senses of the word animate. And you know the drill with YouTube, if you want to stay posted about new videos, subscribe, and click the bell to receive notifications (if you're into that).

If you are new to this channel and want to see more, a good place to start is this playlist: https://goo.gl/WmnCQZ

Various social media stuffs:
Website: https://www.3blue1brown.com/
Twitter: https://twitter.com/3Blue1Brown
Patreon: https://patreon.com/3blue1brown
Facebook: https://www.facebook.com/3blue1brown/
Reddit: https://www.reddit.com/r/3Blue1Brown

Tagged under: math,mathematics,3b1b, blue brown,3 blue 1 brown,topology,borsuk ulam

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