Is teleportation possible?

In Star Trek, people are simply beamed from one place to another at the push of a button. What sounds like pure science fiction is actually already reality today thanks to quantum physics … At least, at the level of a single photon.

How great would it be if you didn’t have to waste another second commuting or travelling by car, bus, train or plane when instead – just like in Star Trek – you could simply be beamed anywhere you wanted to go at the push of a button? To put it another way, what would it be like if matter could also be transmitted wirelessly just like information can? That will surely remain a pipe dream for the foreseeable future. Or will it?
As it happens, physicists today are already in a position to at least beam the basic characteristics of matter (or “teleport” them, to use the correct parlance of the profession).

In two places at once

The basis for the technology is in one of the most spectacular quantum physics phenomena: entanglement. This describes the characteristic whereby two particles behave not as two independent physical objects, but rather as a single one. Entanglement cannot be understood merely in spatial terms: entangled particles correlate to one another on the basis of their characteristics. If the characteristics of the one particle are changed, this means that the other particle will change accordingly at the same time, irrespective of where it is situated. In the case of light particles (photons), it is possible to generate such entanglement by using a laser array with a special crystal to split a single particle into two photons.
Such entanglement can be used to transmit information from one location to another without any loss of time, or so the theory goes. Every measurement which changes the state of the one particle will result in the state of the other particle being changed immediately, regardless of how far apart the two particles are. This process has been known as “quantum teleportation” for a number of years now.

Teleportation across hundreds of kilometres

Last year, Chinese researchers succeeded in using this method to teleport information about the state of photons from a ground-control station to a satellite in space. In theory, it might even be possible to teleport information on the state of a human being in the same way. This would actually enable “beaming” as we know it from Star Trek. For this to work, all you would need to do is decode every single one of a person’s quantum states, send this information to the target location and “imprint” atoms with the same chemical elements.
 

Humans are just too complex

Two major problems are yet to be solved, however. Firstly, a vast amount of energy and extremely complex calculations would be required to teleport a human being. Researchers at the University of Leicester in the UK have crunched some numbers to answer this question: due to the fact that 10 billion bits are required just to describe a single human cell, the data volume for a person of average height and weight would come to around 2.6 x 1042bits – in other words, 2.6 with 42 zeroes behind it. Merely transmitting this information at a cycle rate of 30 GHz would take 350,000 times longer than the existence of our universe.
In other words, you’d be quicker to walk. And even if the rate were to be increased to reduce the duration of travel to a few thousand years, our planet’s energy resources would have been depleted within a single second. Nor would this solve the second problem: what happens to the person at the place of transmission when they arrive at their destination?
According to quantum physics, the original would be deleted and would cease to exist. Who in their right mind would actually be prepared to test a teleportation machine like this? Sadly, in light of all that we know today, it seems extremely unlikely that we will ever be transported to our desired destination simply by uttering the words “Beam me up, Scotty”. Nonetheless, teleportation is well worth all the attention it is afforded, but not for transmitting objects. Instead, quantum physics could be used to create fast computers and achieve lightning-speed data transmission by today’s standards. That’s what you might call wireless communication at its best.

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This article is also available in German language. Click here for the German version.