A tangent from my main thread: here is a surprising fact about polyhedral self-duality.
It’s possible for a polyhedron to be self-dual, but only in such a way that applying the duality map twice DOESN’T return the polyhedron to its starting position.
Here’s the paper (from 1989), but because it’s 2026 I’m going to make a 3d-printable version of this polyhedron. Hopefully that won’t take tooooo long – bear with me.
https://www.sciencedirect.com/science/article/pii/0012365X89901441
robinhouston
npub1wj…7nda9
2026-01-20 19:10:00 UTC
Author Public Key
npub1wjc42kn5sa2pek0h5gfygwrs2s6r7cyr7l2mlpna529pkff97jzs97nda9Published at
2026-01-20 19:10:00 UTCEvent JSON
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"content": "A tangent from my main thread: here is a surprising fact about polyhedral self-duality.\n\nIt’s possible for a polyhedron to be self-dual, but only in such a way that applying the duality map twice DOESN’T return the polyhedron to its starting position.\n\nHere’s the paper (from 1989), but because it’s 2026 I’m going to make a 3d-printable version of this polyhedron. Hopefully that won’t take tooooo long – bear with me.\n\nhttps://www.sciencedirect.com/science/article/pii/0012365X89901441",
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