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Mathematicians have found a hidden 'reset button' for undoing rotation

(www.newscientist.com)
184 points mikhael | 1 comments | 16 Oct 25 15:47 UTC | HN request time: 0s | source
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dukeofdoom ◴[21 Oct 25 21:13 UTC] No.45661800[source]▶
This made me wonder if there are knots you can't untangle.
replies(2): >>45662307 #>>45663224 #
1. jonathrg ◴[21 Oct 25 23:46 UTC] No.45663224[source]▶
Every (mathematical) knot is one that can't be untangled, by definition.

Every knot with a cut can be trivially collapsed go a point by moving one of the endpoints to the other one through the path of the knot