Cardiod in a Cup



Cardiod in a Cup

Sarah Nemec-Nelson and I were having dinner over the holidays, and I was surprised to see this shape when I glanced at my coffee cup.  It's a cardiod!  In this case, it was the result of distant light reflecting off the conically shaped mug.

Relevant Links

Wikipedia:
https://en.wikipedia.org/wiki/Cardioid
https://en.wikipedia.org/wiki/Caustic_(optics)
https://en.wikipedia.org/wiki/Caustic_(mathematics)

Rolling Circles and Balls, a nice series by John Baez
https://johncarlosbaez.wordpress.com/2012/08/31/rolling-circles-and-balls-part-1/

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