The man with 1,000 Klein Bottles UNDER his house

Alex Bellos discusses how the Incans used knots in string (Quipu) to record numbers.Check out Brilliant (get 20% off their premium service): https://brillian...

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Science objects with Brady: http://bit.ly/Objectivity

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This video features Cliff Stoll, the man behind ACME Klein Bottles: http://bit.ly/ACME_Klein