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

Mathematicians have found a hidden'reset button' for undoing rotation Can you undo a spinning top? Imagine spinning a top and then letting it come to rest. Is there a way for you to spin the top again so it ends up in the exact position it started, as if you had never spun it at all? Surprisingly, yes, say mathematicians who have discovered a universal recipe for undoing the rotation of nearly any object. Intuitively, it feels like the only way to undo a complicated sequence of rotations is by painstakingly doing the exact opposite motions one by one. But Jean-Pierre Eckmann at the University of Geneva in Switzerland and Tsvi Tlusty at the Ulsan National Institute of Science and Technology (UNIST) in South Korea have found a hidden reset button that involves changing the size of the initial rotation by a common factor, a process known as scaling, and repeating it twice.