Bizarro Rock - Can you solve Bram Cohen's geometry challenge?
Channel: OskarPuzzle
Date: 2023-05-14

Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://i.materialise.com/en/shop/item/bizarro-rock or at https://www.shapeways.com/product/NHHCCPB6N/bizarro-rock   Bizarro Rock was a design challenge by Bram Cohen in 2019. The object was to design a cube-like object with two traperzium faces, and two-plus-two kite-shaped faces. Whereas each face has a mirror symmetry, the object as a whole has only a two-fold rotation symmetry. The object itself is intended as puzzle: find out the symmetry of the object. Here, the mirror symmetries of the individual faces are intended as red herrings.

Alas, Bram's challenge is unsolvable. If one requires all six faces to be flat, then the resulting object turns out to be flat as well, with all of its faces in the same 2D plane. The challenges is solvable, if we allow two kite faces to be not flat. In that case, the "what symmetry" challenges becomes quite easy to solve, as everybody can see the two non-flat faces.

Copyright (c) 2023, M. Oskar van Deventer.

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