This video goes through the proof using the free group F_2 sitting inside SO(3), without mentioning it as such.

This video goes through the proof using the free group F_2 sitting inside SO(3), without mentioning it as such. I hadn't heard of Ian Stewart's Hyperwebster before, but it's a really nice lead-in. Jump to 8:12 if you're happy with Cantor's diagonal argument and Hilbert's hotel and want to skip definitions of countably/uncountably infinite.

#scienceeveryday   #mathematics  
https://youtu.be/s86-Z-CbaHA

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  1. Michael NelsonAugust 2, 2015 at 10:45 PM

    I remember when I first learned about the Banach-Tarski paradox.  It really made a big impact on my conception of Mathematics at the time.  Of course, my conception of Mathematics is always changing!

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