A friend of mine sent me a link to this picture. I looked at it for a little while, and can’t figure out what’s going on. Anyone have any insight?
For what it’s worth, I believe you can do something similar with a square. If f[sub]n[/sub] denotes the nth Fibonacci number, and you have an f[sub]n[/sub] by f[sub]n[/sub] square, you can cut it up to form an f[sub]n+1[/sub] by f[sub]n-1[/sub] rectangle. Presumably this is the same phenomenon–what is it?
This one is so old it has whiskers on it. I’ve seen it many times.
The area of the missing square is the same as the area of the black lines that delineate the various colored shapes. When the shapes are rearranged the right way, there appears to be a missing square, but it’s just a result of the rearrangement.
If you don’t have a straight edge or understand the equations, just look at the point where the two triangles meet. On the top figure, that point is on a grid point, but the same point on the lower figure is clearly within the red triangle. Likewise, the point where the two triangles meet on the bottom figure is also on a grid point, but the corresponding point on upper figure is clearly outside the figure.
This is in some ways similar to the Banach-Tarski paradox (which doesn’t “cheat” like these others do, with triangles that ain’t triangles, and squares that ain’t squares, and is much more impressive, too, IMO).
The Banach-Tarski theorem says, in effect, that you can take a ball the size of a BB, cut it up into finitely many pieces, then put those pieces back together to form a ball the size of the Sun!
The only catch is that those pieces are very bizarre. In fact, they’re so pathological that you can’t even define a volume for them.