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Is it possible to build a metal wire hollow sphere whose shadow from a nearby point light source projects the 2d conformal maps of the Riemann Sphere on a flat wall?

I believe that in theory it should be possible, but I was not sure if there would be any physical impracticabilities that would limit such a shadow project.

linuxfreebird
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1 Answers1

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This can be done. For example, see

https://www.shapeways.com/model/1480313/grid-stereographic-projection.html

The technical name for this way of "casting shadows" is called stereographic projection. See

and so on.

Sam Nead
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  • Thanks for the answer. In this video you provided https://www.youtube.com/watch?v=VX-0Laeczgk can the cage be flipped 180 degrees and still provide visible shadow of the inverted conformal map? – linuxfreebird Aug 14 '14 at 20:16
  • Yes. This is illustrated at minute 2:00 in the following video. https://www.youtube.com/watch?v=0z1fIsUNhO4 -- the entire video is really excellent, by the way. – Sam Nead Aug 14 '14 at 20:27