A Quantum Entanglement Breakthrough

Scientists at ANU may be on the verge of solving one of the holy grails of science fiction – teleportation – according to  a recent online article by Samuel Cardwell, a technology writer at News Limited.  A research team from the ANU’s ARC Centre of Excellence for Quantum-Atomic Optics, lead by physicist Dr. Jiri Janousek has created beams of light that have the property of quantum entanglement, explained by the writer as:

“a process in which two objects are linked together in such a way that any changes to the properties of one can be measured from the other regardless of the distance between them.”  – Tech News article, June 22nd, 2009 (See the ANU News article here)

Just think about the above statement for a moment.  Imagine that I have an object: A (let’s make it a spinning gyroscope) and you have an identical, entangled second object: B, say one kilometre away. Quantum entanglement says that if I measure the direction that my gyroscope spins I will be able to instantly determine the direction of spin on your  gyroscope.  As long as A and B remain entangled this ability to measure spin direction remotely persists, no matter where either object ends up, even if separated by, say, the distance from the Sun to Earth, or even Betelgeuse.

Einstein referred to this effect as “spooky actions at a distance**”  (Ger. – spükhafte Fernwirkungen) when writing to physicist Max Born.  He was expressing doubts about quantum theory because he believed that physics should represent “a reality in time and space”, a tangibility which the concept of quantum entanglement seems to ignore.

(**Mentioned in: Clegg, Brian (2006). The God Effect: Quantum Entanglement, Science’s Strangest Phenomenon. St Martin’s Press, New York.  P. 3)

Quantum entanglement speaks to a lot of phenomena we experience as humans.  The excitement that most little boys feel when they first get their hands on a radio- controlled car or a train set can be explained in terms of our basic beliefs about the locality of action and cause and effect.   Being in control of a remote object for the first time is contrary to what we believe about the mechanics of existence; that spatial events generally happen due to a visible cause, such as turning a door-handle to open a door.  The very concept of magic as illusion relies on the idea that we can’t really believe what our eyes are telling us when a magician makes a solid object “disappear”. Here too, our basic belief about causality is violated – in this case by some clever distraction or sleight of hand.  This is nicely illustrated in the 2006 film “The Prestige” where Hugh Jackman, playing a stage magician in Victorian England, collaborates with real-life physicist Nikola Tesla (played by David Bowie) to create an illusion called  “The Transported Man”. Although this aspect of the film is largely fiction, Tesla was certainly interested in remote transmission of energy – perhaps a forerunner to teleportation at the quantum level.

Update, May 22nd 2010: The entangled photon distance has been extended to 16 kilometers in the research quoted in the first Related article below.

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