Singapore Lab Runs Final Rehearsals Ahead of a Big Test

SINGAPORE — Inside a basement kept colder than deep space, the Singapore Institute is running the last rehearsals before a demonstration it has scheduled for the middle of next week, when it intends to show a very large quantum processor working over the Q-Net backbone. The physicist Wei-Lin Tan spent Tuesday not on breakthroughs but on error rates. "The public imagines a switch we throw," Tan said, tightening a coolant clamp by hand. "The reality is a machine that forgets what it is doing millions of times a second, and our whole job is to make it forget a little less." Q-Net, she stressed, secures the channel; it carries no information faster than light and never will. What next week's test would demonstrate is scale, not magic — a processor large enough that its answers cannot be checked by any ordinary computer. Until the demonstration runs, the Institute will say only that it is ready to try, and that trying, this week, means holding a cold thing still.