A puzzle about disentangling knots, folding paper, separating strings and wires, and understanding the connectivity properties of elastic figures. General topology questions are off-topic but can be asked on Mathematics Stack Exchange.

Topology is a branch of mathematics that is sometimes also called "rubber-sheet geometry". Topology studies those properties of geometric figures that remain unchanged under distortions and deformations (like twisting, shrinking, and stretching), as long as no surfaces are torn or cut.

Typical topological puzzles are:

  • Wire puzzles: two or more entangled pieces of more or less stiff wire. The closed pieces might be simple rings or have more complex shapes. Normally the puzzle must be solved by disentangling the two pieces without bending or cutting the wires.
  • Wire-and-string puzzles: where a ribbon or piece of string is added to a wire puzzle

General topology questions are off-topic but can be asked on Mathematics Stack Exchange.