Science: We can beam you up, as long as you're a photon

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The Independent Online
Teleportation - just like in Star Trek - has been achieved in a laboratory. That's the good news, or part of it. The bad news? It has only been achieved with a photon, a single wave packet of light, and it would be incredibly difficult to repeat it with any object that had mass.

However, the work by a team at the Institute for Experimental Physics in Innsbruck could lead to super-fast computers which perform calculations using photons, and work faster than anything our present technologies can manage.

In the experiment, run by Anton Zeilinger, professor of experimental physics, certain physical properties of a photon were transferred instantly to another photon, without any connection or communication between the two.

The experiment requires three photons - the original, and a pair of "entangled" photons, whose quantum properties (known as "spin") are complementary.

When the spin of the original photon and one of the others is measured, the third photon takes on the spin of the first. This means that "information" about the first photon has effectively been transmitted without any signal passing.

Though it seems to violate Einstein's finding that no information can travel faster than light, it is a consequence of quantum mechanics: the "entangled" photons could be a galaxy apart, but measuring one would still mean the other displayed the complementary spin to its partner.

However, it is highly unlikely that teleportation and "beaming down" to planets, as Captain James T. Kirk and the crew of the Starship Enterprise did each week in the television series, will be a reality in the future.

"People are much too large," said Professor Zeilinger.

But the work, reported in the science journal Nature, may lead to "quantum supercomputers" which could process information faster than the speed of light. The next step is to create a cluster of entangled particles in which "superpositions" of information could be stored.

A computer bit is either zero or one. A quantum bit could be in the superposition of zero and one - both at the same time.