The "Bell Telegraph."

Matthew X profrv at nex.net.au
Sun May 9 06:48:34 PDT 1999


'Bell Telegraph' May Enable Cosmic Communications
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By Mike Martin
NewsFactor Sci::Tech,
Part of the NewsFactor Network
August 19, 2002

Einstein's special theory of relativity strictly forbids anything from 
traveling faster than the speed of light. A quantum mechanical Bell 
telegraph, however, may defy this prohibition with a twist -- literally.

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No ; not that one...
The future of telecommunications may hinge on a clever new version of a 
device from its past, physicists claim. What the Bell telephone is to 
communication across town or overseas, the Bell telegraph -- named for 
British physicist J.S. Bell -- may become to communication across the solar 
system or even the Milky Way.

John Bell first proposed that the strange properties of quantum  mechanics 
might permit subatomic particles to interact instantaneously over distances 
so vast that signals between the particles had to travel faster than light 
speed.

"A device that transmits information faster than light speed has always 
been possible, at least in theory," telecommunications engineering 
professor and former Bell Laboratories director Ira Jacobs told News 
Factor. "In practice, such a device would present monumental engineering 
hurdles that might be overcome by futuristic engineers," he added.

Defying Einstein with a Twist

Einstein's special theory of relativity strictly forbids anything from 
traveling faster than the speed of light. A quantum mechanical Bell 
telegraph, however, may defy this prohibition with a twist -- literally.

The so-called up and down "spin" states characteristic of quantum particles 
would substitute for telegraphic dots and dashes. Spin is a particle's 
intrinsic angular momentum and may be visualized as a left or right-handed 
rotation -- or twist -- about an imaginary axis.

In theory, a Bell telegraph could send an instant signal from a particle on 
Earth entangled with a second particle on a planet light years away -- a 
special configuration called a "Bell state."

Spooky Physics

"A Bell state is a particular kind of quantum state that describes two 
particles in which measurement of some quantity in one of the particles 
instantly affects the distant particle, no matter how far away it is," 
physicist Daniel Badagnani, a visiting professor with Argentina's National 
Research Council (CONICET), told NewsFactor.

The very act of observing the Earth-bound particle's spin -- up or down -- 
instantaneously causes the distant particle to occupy the opposite spin 
state, a circumstance of quantum mechanics so mystifying Einstein called it 
"spooky."

Spin "up down up" measurements on the Earth-bound particle instantly become 
spin "down up down" readings on the distant particle. Assigning dots to 
"spin up" and dashes to "spin down" leads to a "dash dot dash" with another 
amazing twist -- the dots and dashes appear instantly to a receiver -- no 
matter how far away.

Quantum Hurdles

However, future engineers will have to overcome another strange quality of 
quantum phenomena to construct a functional Bell telegraph. In theory, spin 
up is a "pure" state, a certainty like the left- or right-handed rotation 
of a planet or spinning top. In practice, however, quantum spin exists as a 
high or low "probability" of up or down, never guaranteed until an actual 
measurement occurs.

Quantum states may be visualized as fuzzy, statistical "waves" that only 
collapse into hard data after a definitive observation -- hardly the stuff 
of reliable information. "Due to the probabilistic outcome of the collapse, 
or quantum measurement, no information can be transmitted through a 
collapse," University of Missouri physics professor Peter Pfeiffer told 
News Factor.

'Informed Crazies' Agree

To surmount this hurdle, Daniel Badagnani has searched for an "ingenious 
setting that could distinguish between the pure state and the statistical 
mixture," he explained. The prospect of such an innovation heartens 
National Science Foundation Electrical and Communication Systems program 
director Paul Werbos.

"I am one of those informed crazies who thinks that there is a 2-to-1 
chance we should be able to build something to do what Badagnani wants to 
do, sooner or later, by exploiting basic phenomena of quantum dynamics and 
quantum measurement," Werbos told News Factor. 





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