How quantum navigation could give militaries a backup when GPS fails

The article discusses the Pentagon’s efforts to develop quantum navigation systems as a resilient alternative to GPS, which is vital but vulnerable to jamming and spoofing. GPS, originally designed for military use during the Cold War, has become integral to both defense and civilian applications. However, its reliance on faint satellite signals makes it susceptible to interference, a weakness highlighted by recent incidents such as GPS disruptions over Bulgaria and ongoing jamming in conflict zones like Ukraine and the South China Sea. Traditional inertial navigation systems (INS) serve as a backup but suffer from cumulative errors over time, making them insufficient for precise, long-term navigation without GPS. To address this vulnerability, DARPA awarded $24.4 million to the Australian startup Q-CTRL under its Robust Quantum Sensors (RoQS) program to develop quantum navigation systems that do not depend on satellites and can function reliably in combat environments. These quantum sensors leverage the extreme sensitivity of atoms cooled and trapped by lasers to measure fundamental forces like acceleration and gravity with high precision