Can you fake your check‑in at the office or a scenic spot simply by installing a “virtual location” app on your phone? This trick may soon become completely unworkable.

Recently, the University of Science and Technology of China (USTC) announced that teams including the Hefei National Laboratory and USTC have completed the first full experimental verification of quantum‑secure positioning. The system achieves positioning accuracy better than 75 meters, reaching the spatial scale of a single building. The relevant findings were published online in the international academic journal Nature Physics.

Every day, we rely on location information for mobile phone navigation, vehicle positioning and other services. Yet the ability to locate a device does not guarantee the authenticity of its reported location. In scenarios demanding high trust in location validity, existing technologies remain vulnerable to exploitation: location data can be forged via copying and relaying signals.

So how do we verify that a target is truly at a given location? Quantum‑secure positioning offers a new solution. In simple terms, it leverages the no‑cloning property of quantum information, together with relativistic constraints on time‑space relations, to securely verify a target’s position. Compared with conventional positioning methods, this approach provides stronger protection against location spoofing.

Nevertheless, practical implementation of quantum‑secure positioning faces substantial challenges. Quantum signals suffer transmission loss, and equipment introduces bit errors. Even minor response delays during positioning can degrade final accuracy.

The experiment finally attained positioning accuracy better than 75 m, meaning trustworthy location verification can be narrowed down to the scale of an individual building.

According to the research team, quantum‑secure positioning can be applied to secure tracking of high‑value assets and target identification in disaster rescue operations. Going further, location itself can serve as a kind of “security credential”. For instance, a trusted geographic zone can be predefined: financial transactions, access to sensitive data or permission grants will only be permitted once a device or person is confirmed to be physically present within that zone. In other words, in the future, where you are may become part of identity authentication and security verification, just like passwords and fingerprints.

Source: Hefei Daily