Computer Gives Correct Answers When Switched “Off”

(Hmmm, that sounds like some computers I know. You know what I mean: they work better when not even turned on.)

That’s what this computer experiment demonstrated: a quantum computer that delivered correct answers 1/3 of the time… when no data was input. What sounds like a trip to Madam Woowoo’s Voodoo Parlor and Seance Emporiumis really quite something else.

Physicists have long known that quantum computers have the potential to race through calculations trillions of times as fast as ordinary computers do. Now, it seems that those machines may not have to calculate at all to deliver answers.

While it might appear to be intuitive that the seemingly random nature of quantum mechanics would be able to return accurate calculations only half the time, at best, researchers at the University of Illinois at Urbana–Champaign have built a simple quantum computer that performs simple database searches. The intriguing thing is that,

… about a third of the time that, with no photon going into the computer, and thus no search, the computer had yielded the correct answer to the question: Was there a mismatch between the incoming photon and the chosen database location?

Hmmm. That’s better than I used to do with “always bet the leading apprentice jockey to show”…