There is a formula so strongly associated with one shape that seeing it almost makes the shape appear in your mind:
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It is the surface area of a sphere.
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A sphere of radius r, with its diameter d shown through the center.
Now imagine something that looks nothing like a sphere: no spherical symmetry, no fixed axle, and a surface assembled from straight line segments. Push it across a table and it sways as it rolls, continually changing orientation while a line of contact travels across its surface.
Very cool and informative and friendly explanation. Articles like this are why I joined Medium. One day, I will be able to write like this guy. Thank you for this great article. You're one hell of an academic. Now following you on Medium.
