Now that the door to the quantum world has been opened with our quantum computer blog I thought I’d share some more information regarding this fascinating field and how it might affect technology. What I’m referring to here is quantum entanglement, this is what Einstein referred to as a spooky action from far. In the original quantum computer blog I wrote, I mistook this for the quantum leap which has now been corrected. If you’ve read about articles referring to teleportation being achieved this is how they’ve done it.
First, what is quantum entanglement? This is when two particles share a magical connection and by magic I mean they can’t explain it at this point, although there are theories. When they force two particles to interact with each other they establish this connection and it can be measured because each particle has a spin and when two particles entangle they’ll have opposing spins. So when one particle has a spin up and the other particle will have a spin down.
Einstein thought that there was no communication between these two particles after they were entangled but rather that once the connection was made that the particles would always have opposing spins. This could be visualized by picturing two shoes a right and left one being put into two boxes and sent to different locations. No matter how far they go when the boxes are opened one will have a right foot and the other will have the left foot.
Quantum theory on the other hand believed that there was a connection and that if we could affect the spin of one particle that the other would be instantly changed as well. This would also happen instantly, no matter how far the two particles are from each other and regardless of anything that was placed between them. This doesn’t mean just two particles a few feet apart with a wall between them but particles that could be on the other sides of the universe from each other with planets, galaxies and anything else between them as well. This defied the theory that Einstein had of nothing being able to travel faster than light which theoretically would have meant time travel (a totally different topic that is interesting on its own).
Today we know that Einstein was wrong and that the quantum theory was correct on this assumption. It was actually proved by someone who was in Einstein’s camp on this theory and set out to prove him right but instead did the opposite. Unfortunately Einstein wasn’t around to find this out as it was discovered sometime after he passed.
We’ve also pushed this envelope even further and achieved teleportation of a particle over several hundred kilometers. In order to do and prove this scientists first establish a connection between two particles, a photon (a light particle) in this case. Once this is done they use a laser light to send one of these particles to another location where they can monitor the particle and confirm it’s the same particle due to its relationship or connection with the first particle which remained at the source location. They then introduced a third particle which is entangled with the first particle and measure the differences between the two, this information is then used to establish a connection on the second particle which now recreates the particle we wish to teleport. In the process of doing this the particle being teleported is destroyed at the source location and recreated at the destination.
We’re now left with a big question since the particle being teleported was destroyed and recreated is it the same particle. Since it seems to have all the same information contained by the original particle we can speculate that it is but since the first particle was destroyed and the second one was recreated, is it more of a clone instead? The next question is when can we try to do something like this on matter, this might not happen in our lifetime or at all but because we can do it with something like a photon it also means that there is a possibility, we just need stronger technology to handle the countless particles involved in something like this.
Although sending particles over vast distances is pretty cool and teleportation sounds wicked, the more practical use with something like this would be in communication. If we can find a way to incorporate these entangled particles, we would not only have instant communication without delay between devices but also a more secure one. The security behind that communication could in theory be uncrackable because only the entangled particles would be communicating with each other and there is nothing in between to catch or listen to, we could always encrypt the communication as well to add an extra layer of security if we chose too.