The Brunnian Circles
are made of 3 interlocked rings.
Brunnian means that even though the 3 circles are interlocked, no two of them are linked (in other words, remove just one of them and the two other ones will fall apart).
The red circle in on top of the blue one, the blue one on top of the green one and the paradox is that the green circle is on top of the red one.
This is possible because they are pseudo-circles: in reality they do not stand in a plane but are "waved".
Their diameter is 4cm and they thickness 5mm.
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