How could a teleportation of people be possible?

Teleportation in the quantum realm

While beaming people has so far been a utopia, the teleportation of particles has long been a reality. Because the quantum physical phenomena of entanglement and superposition make changes in state and information exchange possible even over great distances.

Quantum teleportation is based on the generation of entangled photons, atoms or ions. The quantum states of such pairs of particles are coupled with each other in such a way that the change of state of one automatically causes that of the partner. This happens instantaneously and regardless of the distance. Albert Einstein therefore referred to this phenomenon as a “spooky long-distance effect”.

Instantly from A to B

For the "beaming" of digital quantum information, entangled particles are created that encode the information, for example in terms of its polarization - one direction then stands for zero, the opposite direction for one. One of the partners is then sent to the destination via fiber optics, submarine cables or even through the air. If the state of the particle is measured at the starting point, this also causes a change of state in his partner at the destination - he instantly assumes the state of the “transmitting particle”.

The quantum information is transmitted with almost no loss of time - regardless of the distance of the entangled particles. "Quantum teleportation is comparable to beaming in the science fiction series Star Trek," explains Andreas Wallraff from the Swiss Federal Institute of Technology in Zurich (ETH). "The information does not travel from point A to point B. Rather, it appears at point B and disappears at point A when you read it." So far, however, the amount of information that can be transmitted in this way has been extremely limited - mostly only a few bits .

One of the partners must always be there

Does quantum teleportation possibly open up a "loophole" to make beaming people possible one day? Unfortunately, there are two major hurdles here. The first: In order to teleport information such as a quantum key or arithmetic operations, one of the two entangled parts must always first be brought to the destination - using "normal" means, for example via data line. Only when these coupled particles are in place can the information be instantaneously shared between sender and receiver.

However, this means that quantum teleportation is also subject to the time restrictions of classic transmission - and that the appropriate infrastructure must always be available at the destination. Beaming Captain Kirk or Picard from board the Enterprise to the surface of a strange planet would only be possible if all the atoms of these people had been scanned, their quantum information had been transferred to entangled particles and then had been sent down beforehand using conventional means. Then, however, the whole beaming would be superfluous and Kirk or Picard would be down faster with the space shuttle.

Too dynamic for the quantum effects

We humans are the second problem: In us, the individual atoms and molecules are exposed to so many interactions and disturbances that all quantum-physical superpositions and entanglements would collapse immediately. Even under laboratory conditions, these states can only be maintained under carefully controlled conditions that are shielded from interference. In the dynamic human system this would be utopian. “We're not quantum objects,” says US physicist Lawrence Krauss.

In his opinion, beaming people is a fascinating idea, but unfortunately one of the Star Trek technologies that is least likely to be implemented. "In order to build a transporter, we would have to heat matter up to a million times the temperature in the core of the sun, generate more energy for the machine than is available to all of mankind, increase computer power by a quadrillion-fold and circumvent the laws of quantum mechanics," states Krauss in his book “Physics of Star Trek.

As tempting as the prospect of teleportation as a fast transport solution is, even our descendants in the distant future will have to work very hard to ever implement such a technology.

September 11, 2020

- Nadja Podbregar