Quantum computers could usher in a crisis worse than Y2K

Quantum computers could cause a global security crisis that makes the once-feared millennium bug, or Y2K, look quaint. This infamous computer risk was averted through the persistent behind-the-scenes work of engineers across the world, but whether the new threat will be tackled similarly is an urgent yet unresolved question. Most digital communications and transactions are protected by cryptography based on mathematical problems that are unsolvable by conventional computers but are solvable by a sufficiently capable quantum computer. Researchers have understood this since the late 1990s, but the day when this capable-enough quantum computer comes online - or Q-Day - was thought to be very far in the future. Working quantum computers are now a reality, and recent leaps in how to use them are bringing Q-Day ever closer.