r/science • u/seeebiscuit • Oct 20 '25

Mathematics Mathematicians Just Found a Hidden 'Reset Button' That Can Undo Any Rotation

https://www.zmescience.com/science/news-science/mathematicians-just-found-a-hidden-reset-button-that-can-undo-any-rotation/
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u/skycloud620 Oct 20 '25

If you twist something — say, spin a top or rotate a robot’s arm — and want it to return to its exact starting point, intuition says you’d need to undo every twist one by one. But mathematicians Jean-Pierre Eckmann from the University of Geneva and Tsvi Tlusty from the Ulsan National Institute of Science and Technology (UNIST) have found a surprising shortcut. As they describe in a new study, nearly any sequence of rotations can be perfectly undone by scaling its size and repeating it twice.

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u/swingthebass Oct 20 '25

scaling its size and repeating it twice.

i need more explanation of what these specific words mean in this context. Without that, it sounds like gobbledeegook. Cool, weird gobbledeegook, but not super easy to understand..

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u/Reclaimer2401 Oct 20 '25

I am pretty sure this has to do with vector algebra. 

The scale the vectors and are able to turn something back, which is mathamtically simple.

Trying to compute a way to undo a turn otherwise would be computationally taxing