Thursday, November 30, 2006

Pardon Me, My Tardis Is Double-Parked

I wasted time, and now doth time waste me. ~William Shakespeare, Richard III

John Cramer of the University of Washington thinks he can send information back in time using quantum entanglement and “spooky action at a distance.” Once again, we see that, if you want to do something weird, you only need to go into the quantum world.

Mr. Cramer is not attempting to send a particle back in time. Instead, using a complicated scheme of detection, he hopes to show that a one of a pair of entangled particles has sent its state back into time to alert its partner as to what the partner's state should be. The researchers are also looking for a “signal” of some sort that passes between the entangled particles so that one knows what is going on with the other, although the article doesn't describe how they intend to detect that signal.

Back in “Spooky Entanglement”, I talked about how two quantum particles, a couple of photons for instance, can be “entangled” so that disturbances affecting the state of one immediately affect the state of the other, even if they are separated by vast distances. This is what Einstein derisively called “spooky action at a distance.” The effect is real; it's even been used, as explained in my previous piece, to teleport a particle from one place to another.

To review briefly, if you measure a quantum particle you disrupt it. If you learn it's location, you can't accurately determine it's momentum, for instance. A photon acts as both a wave and a particle. If you set up an experiment to detect its wave properties, you won't see its particle properties; if you set a detector to look for particle properties ahead of the wave detector, then you will only see particle properties. If you have two entangled photons and you detect one as a particle, the other should exhibit particle properties as well.

The U of W experiment will use that to show information going back in time by setting up a detector that will show photon A as a particle or a wave. Photon B, meanwhile, will be taking a leisurely trip through a couple of 10 km spools of fiber-optic cable to another detector. That second detector can be manipulated in some manner to detect it as either a particle or a wave. In Mr. Cramer's theory, photon B has to send the information about its pending state back in time 50 microseconds to photon A so A knows what property to exhibit at its detector.

Well, maybe. All we really know is that measurement of A will disrupt it in a manner that will be duplicated in B at the instant of measurement. However, measurement of B will also disrupt in a way that will be duplicated in A. But, since we've disrupted A already, we really can't tell anything about what B's measurement means without examining A again. In other words, the measurements are independent events. Just because you try to make B behave like a wave and A happened to look like a wave doesn't mean that the B measurement was transmitted back.

To put it another way, I don't think this is going to work.

It doesn't really matter, because the late Dr. Isaac Asimov introduced the world to Thiotimoline, a chemical that dissolves 1.12 seconds BEFORE water is added to it, in 1947.

By the time Asimov was working on his doctorate in Chemistry, he was already being published in “Astounding” magazine (later known as “Analog”). He wrote three stories about the chemical, the first of which was a scholarly-looking document with the ponderous title, “The Endochronic Properties of Resublimated Thiotimoline.” The third of the stories was a “speech” given before the “American Chronochemical Society” explaining the dangers the chemical posed to the Free World if it was in the hands of the Soviet Union.

Because Thiotimoline dissolves before water is added, you could use it to predict events. You begin with the “endochronometer”, a device which automatically delivers the water to the Thiotimoline, which dissolves 1.12 seconds before the water hits it. You could hook a second endochronometer to the first which, when the chemical in it dissolved, triggered the first to release its water. You could create a battery of these devices to extend the time from the triggering of the first endochronometer to the dissolving of the Thiotimoline in the last. In fact, about 77,000 of them would result in a process taking about 24 hours.

The practical upshot of this is that you could forecast the result of an event by deciding that, upon one outcome you would trigger the battery while on another you would not. Then, if you checked the last endochronometer 24 hours before the event, you would know the outcome based on whether the Thiotimoline had dissolved or not.

Suppose you wish to bet on a football game. If team A wins, you will trigger the endochronometer batter at 7 PM the day of the game. If they lose, you will do nothing. You check the last endochronometer at 7 PM the day before the game; if it has dissolved, bet the farm on team A. Otherwise, put your 401k on team B.

Of course, Thiotimoline is a fiction, but in one of Asimov's stories on the subject, he builds a wondrous sequence of events to demonstrate its potential for international catastrophe.

At the time he wrote the first story, which had the look and feel of a scholarly piece, Asimov's doctoral review was coming up, and he was naturally concerned that some of the thesis examiners would not be amused by a doctoral student taking time from his work to write a lampoon thesis, so he asked John Campbell, editor-publisher of “Astounding”, to publish the story under a pseudonym. Campbell, who enjoyed the story enormously, agreed then promptly forgot, so the story was published under Asimov's name.

The story was an immense success, and, according to Asimov, the New York Public Library was pestered immediately by students wanting to check the (fake) references from the “article” so they could learn more about the subject. While he should have been pleased, Asimov was devastated. He figured that the academicians at Columbia, where he was taking his doctorate, would not be amused at his lampoon of scholarly writing.

He was, therefore, relieved as he went through his orals that the professors treated him well and made no reference to his story. As he reached the end of the exhausting process, one of the professors intoned solemnly, “Asimov, can you tell us something about the endochronic properties of resublimated thiotimoline?” Asimov, seldom a man at a loss for words, was unable to answer because he was laughing so hard.

He got his PhD, demonstrating that, at Columbia at least, even stuffy professors have a sense of humor.

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