Shadows are the topic of a
book recently reviewed on the Popular Science website (The
Shadow Club by Roberto Casati) - it's nothing to do with
the book, but here's a stunning optical illusion featuring shadow:
This optical
illusion is reproduced with the permission of Professor Edward Adelson of
M.I.T.
Click here for details on the Professor's site.
Thanks also to Andy Grüneberg for bringing this to our attention.
This is simply the best optical
illusion we've ever seen. It illustrates why the really interesting thing
about shadows is not what they are - simply the absence of light, contrasted
against an area where light is hitting - but how our brains perceive them:
