Chinese scientists have successfully used quantum teleportation to send photons into space.
The experiment was the second this month to use quantum teleportation to send photons to the Micius satellite which is positioned about 1400 kilometres above Earth. It is the longest distance over which quantum teleportation has ever occured.
Quantum teleportation sounds great. But what is it?
Let’s start with photons, which are essentially particles of light (But what’s light? Shhhhh, we actually aren’t too sure).
Using quantum physics – which Albert Einstein called “spooky” – scientists can entangle photons.
Entangled photos are weird because theoretically you can move them far apart and measure one and, at that moment, the other particle will get information of the other particle’s state, no matter how far away it is.
Gizmodo gives a pretty good analogy for this weirdness:
As an example, let’s say there are two bags, and each has one of two balls, red or green. You give a bag to your friend. Quantum mechanics only gives the probabilities that your bag contains either ball colour, and that’s all you know before making the observation. At human scales, each bag already contains a red or green ball. Quantum mechanics says both balls are red and green at the same time—until you look. That’s weird on its own, but it gets worse. If you look at your ball, the other ball automatically takes on the other colour.
The Chinese researchers basically prepared the two bags from the analogy above and placed one on Earth and once in the Micius satellite. Using the link between the bags, they can then send information between the two locations.
Think of it like this: By knowing something about the photon on Earth, we can know something about its entangled counterpart on the satellite. This amounts to a kind of teleportation – just probably not the kind you had in mind.
So what can we do with it?
The researchers say that this type of communication is an important step towards a “quantum internet”, which will be theoretically unhackable and a major leap forward in cyber security.
Quantum teleportation and quantum encryption keys? Check and check. https://t.co/WEww6E0dnU
— Science News (@ScienceNews) July 10, 2017
But what quantum teleportation won’t do is teleport physical objects. For now, that’s still well in the realm of science fiction.