Round Peg in a Square Hole - Numberphile
Featuring Tadashi Tokieda - more Tadashi videos at: http://bit.ly/tadashi_vids More links & stuff in full description below ↓↓↓ Tadashi Tokieda is a Professor of Mathematics at Stanford...
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I made a square hole in the sheet of paper, and a coaster, a circular coaster. I fold the paper in a mysterious fashion, and I can pass the coaster through the hole, really passes both directions, and I haven't started cheating. It really is going through the hole. And yet when I put these out, the diameter of the coaster is bigger than the diagonal of the square hole. What is going on? I didn't stretch and didn't tear. And yet when I fold the sheet back, in a judicious way, the coaster does go through, the coaster which is bigger than the hole. How is this possible? I am willing to give away the secret for free, on this special occasion. It has to do with the interplay between, the intrinsic, or inner dimension, of the sheet of paper ...
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I made a square hole in the sheet of paper, and a coaster, a circular coaster. I fold the paper in a mysterious fashion, and I can pass the coaster through the hole, really passes both directions, and I haven't started cheating. It really is going through the hole. And yet when I put these out, the diameter of the coaster is bigger than the diagonal of the square hole. What is going on? I didn't stretch and didn't tear. And yet when I fold the sheet back, in a judicious way, the coaster does go through, the coaster which is bigger than the hole. How is this possible? I am willing to give away the secret for free, on this special occasion. It has to do with the interplay between, the intrinsic, or inner dimension, of the sheet of paper ...
