Quantum physics could, theoretically, be used to fulfill the age old desire to teleport. However, any practical use is a an extremely long way off, with scientists only managing single particles so far.
In the video below, minutephysics explain how teleportation could be theoretically possible using quantum physics. Quantum teleportation uses quantum entanglement— a situation where one set of particles is dependent on the state of another. In principle, if scientists create specific sets of particles that are capable of being rearranged into whatever they wish to teleport, they can send partial information about one end of the entanglement — encoded as a quantum state — and thereby produce it in the other end. As an analogy: imagine taking a scan of what you want to transport, sending it to the other entangled particles, and rebuilding it from that.
While being able to transport anything large, like a cat — the example the video uses — is a long way off, scientists have managed to transport a single photon or electron about 100km. The difficulty lies in creating two entangled sets of particles and subsequently transporting one of them without it becoming disentangled.
This is linked to scientists achieving direct counterfactual quantum communication for the first time recently, which operates using the Zeno effect (freezing the situation by observing it) rather than entanglement. In the experiment, scientists successfully transported information using the phase of light.
It depends on what you mean by entanglement. In Quantum Field Theory entanglement refers to two quanta that are created together and whose properties are therefore correlated, so that if one collapses the other does also. In this sense, there is no connection whatsoever with “teleportation”. But let me explain further. First here is what I wrote about quantum collapse in my book:
Schrödinger, on the other hand, wanted to believe that the electron is a wave spread throughout all of space, but he had to face the particle behavior as seen, for example, in a cloud chamber .
We assert that the atom in reality is merely the… phenomenon of an electron wave captured, as it were, by the nucleus of the atom… From the point of view of wave mechanics, the [particle picture] would be merely fictitious. I have, however, already mentioned that we have yet really observed such particle paths… We find it confoundedly difficult to interpret the traces we see as nothing more than narrow bundles of equally possible paths. – E. Schrödinger (, 1933)
Quantum collapse. The answer to Schrödinger’s dilemma is quantum collapse (see Chapter 3). If a field quantum transfers its energy to an atom it must do so as a unit and disappear from all space, no matter how spread out it is. Even if it transfers only part of its energy, it must collapse every time energy is transferred. As Art Hobson wrote, referring to the cloud chamber tracks shown above:
The tracks are made by successive individual interactions between a matter field and gas or water molecules. The matter quantum collapses… each time it interacts with a molecule, while spreading out as a matter field between impacts. – A. Hobson ()
And here’s what I wrote about entanglement:
Quantum collapse can also occur if two quanta are created together so that their properties (spin, momentum, etc.) are interrelated. Such quanta are said to be entangled; if one quantum collapses or changes its state, the other must do the same and it must do it instantaneously. Experiments with entangled photons have demonstrated that when the spin of one photon changes (via interaction with a magnet), the other spin also changes, and it does it at the same time, no matter how far apart the photons are. This is what Einstein called “spooky action-at-a-distance.”
Resolution. In QM there is no way to explain this, but in QFT it is just another instance — a more elaborate instance — of quantum collapse. If one can accept that a single quantum, even if spread over miles of space, can instantaneously collapse, it is not much of a stretch to accept that two entangled quanta can do the same.