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Do you understand quantum computers? Neither do I.

This is the future, and I don’t get it. I am now officially old.

Via Boingboing: Quantum computer solves problem without running program [1] (From eurekalert.org [2])

Utilizing two coupled optical interferometers, nested within a third, Kwiat’s team succeeded in counterfactually searching a four-element database using Grover’s quantum search algorithm. “By placing our photon in a quantum superposition of running and not running the search algorithm, we obtained information about the answer even when the photon did not run the search algorithm,” said graduate student Onur Hosten, lead author of the Nature paper. “We also showed theoretically how to obtain the answer without ever running the algorithm, by using a ‘chained Zeno’ effect.”

Through clever use of beam splitters and both constructive and destructive interference, the researchers can put each photon in a superposition of taking two paths. Although a photon can occupy multiple places simultaneously, it can only make an actual appearance at one location. Its presence defines its path, and that can, in a very strange way, negate the need for the search algorithm to run.

“In a sense, it is the possibility that the algorithm could run which prevents the algorithm from running,” Kwiat said. “That is at the heart of quantum interrogation schemes, and to my mind, quantum mechanics doesn’t get any more mysterious than this.”

Ain’t that the truth.

2 Comments (Open | Close)

2 Comments To "Do you understand quantum computers? Neither do I."

#1 Comment By That Girl On 24 Feb, 2006 @ 15:45

This reminds me of the highly amusing concept in David Foster Wallace’s Infinite Jest where one of his characters, a filmmaker, begins making “reality” films in which the art is that there is no artistry in the portrayal.
He picks his subjects at random and then asks to film them. The next step in his “art” is to just pick the person’s name out of the phone book. The end. Because filming them changed their nature. So not filming them is the true art film.
I probably didnt explain this well. I understand the concept of your post but I probably cant explain that either 🙂

#2 Comment By quixote On 26 Feb, 2006 @ 11:29

Girl, if you understand that post, please explain it to me. Really.

(I like the “reality filming” concept. Not sure I’d spend time watching the movie. ;-}