麻豆淫院

The world is filled with rotating objects鈥攇yroscopes, magnetic spins, and more recently, qubits in quantum computers. For example, the atomic nuclei in our bodies precess at megahertz frequencies inside NMR machines. In practice, it is often desirable to return such a rotating system precisely to its starting point. At first glance, this seems impossible: after an elaborate sequence of twists and wobbles, how could one possibly retrace the path back to the origin?

The astonishing answer is that it is always possible. No matter how tangled the history of rotations, there exists a simple recipe: rescale the driving force and apply it twice. A single application is never sufficient, but applying this doubled, rescaled force guarantees an exact return. Under this operation, the spin鈥攐r the qubit, or any rotor鈥攚ill unfailingly come home.

This discovery was made by Distinguished Professor Tsvi Tlusty from the Department of 麻豆淫院ics at UNIST and Jean-Pierre Eckmann from the University of Geneva, Switzerland. Their study, in 麻豆淫院ical Review Letters on October 1, 2025, reveals that, despite their apparent complexity, rotations conceal a fundamental order.

The mathematical groups describing rotations鈥攌nown as SO(3) for classical objects and SU(2) for quantum ones鈥攁re among the most studied in physics. Yet even within this well-understood framework, the authors identified a new, elegant solution: a perfect reset button.

Why does this matter? Because rotations underpin nearly all modern technology and science. From stabilizing satellites to decoding brain scans, from nuclear magnetic resonance to quantum computing, we constantly task rotators with performing intricate dances. This new result guarantees that, regardless of how complicated the choreography, there is always a way to return the system to its original pose.