WATCH: How quantum teleportation works

By -

Posted by: Tarun Kumar Teleportation is no longer science fiction -
thanks to quantum mechanics scientists can
teleport information securely from one place to
another. The latest episode of Quantum Around
You explains how.
When most people think about teleportation, they
think about someone disappearing in one spot
and appearing in another instantly, Star Trek
style. While that would be extremely useful, so
far scientists haven't found a way to do it.
But what they have managed to do is teleport
information, and in some ways that’s even
cooler.
Quantum teleportation, as its known, is a crucial
area of research because it’s the only way
humans can transmit information completely
securely, with no risk of interception.
To do this, scientists exploit the special
characteristics of quantum entanglement. You
may have heard of it before, but the latest
episode of University of New South Wales
(UNSW) 's Quantum Around You does an
amazing job of breaking down the physics behind
the process.
As Associate Professor Andrea Morello , from
the School of Electrical Engineering and
Telecommunications at UNSW, explains,
quantum entanglement is when two electrons
become linked and lose their individuality. This
means their state or “spin” - which can either be
up or down - is defined only as being the
opposite of each other.
If you split up two entangled electrons, the
person with one can you’re suddenly able to
transmit information from one to the other.
That means you could encode information on a
single electron (an up spin could mean one thing
while a down could mean another, or more
commonly, up could represent a '1' in the binary
code, while down represents a '0'), and the
person with the other entangled electron would
be able to access that information by looking at
what state their electron is in.
So how is that teleportation? What many people
don't realise is that as soon as that information
is transmitted, it disappears from the electron of
the sender and instantly reappears on the
recipient's electron. Ta da! This is because the
sender has to to use another, non-entangled
electron to read the information properly, and as
soon as they do this the entanglement is lost.
But even though this is a pure example of
teleportation, it doesn’t actually contradict
Einstein’s theory of relativity, which states
nothing can move faster than the speed of light.
Watch the episode above to find out why, and
learn more about how scientists are making
information disappear and reappear all over the
world.