Tangloids

Tangloids is a mathematical game for two players created by Piet Hein to model the calculus of Spinors.

Two flat blocks of wood each pierced with 3 tiny holes are joined with 3 parallel strings. Each player holds one of the blocks of wood. The first player holds one block of wood still, while the other player rotates the other block of wood around any axis for 4π radians. Then the first player tries to untangle the strings without rotating either piece of wood. Only translations (sliding) are allowed. Afterwards, the players reverse roles; whoever can untangle the strings fastest is the winner.

ASCII diagram:

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