In a development that scientists are calling the most consequential in computing since the invention of the transistor, researchers announced Thursday the successful operation of a 1,000-qubit quantum processor that maintains coherence for unprecedented durations — a barrier the field has struggled to breach for nearly two decades.

The implications, experts say, are staggering. Modern cryptographic systems protect everything from banking transactions to nuclear command infrastructure. If quantum machines can be scaled to this new threshold, many of those systems would become vulnerable far sooner than governments have planned for.

"We are not saying the walls are falling tomorrow," said Dr. Elena Vasquez, the lead researcher. "We are saying we can now see the walls clearly, and they are closer than anyone thought."