Star Trek Fans, Your Day Has Come: Quantum Teleportation
The sci-fi world has been inspiring humanity to see beyond, envision the impossible for decades. Hollywood in the lead, the major production companies of the entertainment industry have been embellishing our childhood dreams & fantasies. Though now, in the Holocene era, those fantasies do not have to stay that way. Let me break the news to you:
Teleportation is a thing now!
A Brief Summary
Scientists have been trying to achieve what James Kirk and his crew already did for years now via methods related to quantum physics. There have been many attempts; In 2014 the first completely successful trial, with a replication rate of 100%, was attained by Dutch physicists of the Delft University of Technology. Although this is not a recent news, not many are aware that teleportation is possible. So here it comes: The mystical process of making an object disappear and reappear at another place.
The technique the scientists used relies heavily on quantum principles of subatomic particles. For the interested, I will try to explain in the simplest way how this magical undertaking is executed.
A Little Bit Chemistry First
As you know, all the matter in the universe is made up of atoms. Inside these atoms, there exists even smaller subatomic particles: protons, neutrons, and electrons. The protons and neutrons are inside the nucleus of the atom, in the center. The electrons orbit the nucleus on predefined orbits. Subdivisions of orbits are called orbitals and each can only carry 2 electrons at most. The two electrons’ states are affected by each other; this property is called “Quantum Entanglement”.
Quantum Theory & Entanglement
Quantum theory basically investigates how every applied physics rules that allow an exact inspection of matter doesn’t work in a much smaller, atomic scale. In quantum levels, you usually cannot determine an exact property or action. Rather, you can find the probability distributions of every possible state. An object is made up of the combinations of the endless possibilities of states of its atoms. The possible states are called “superposition”.
Consider the famous, Schrodinger’s cat. The cat is inside a box along with a bomb which has a possibility of exploding of 50%. Unless we open that box, we cannot know if the cat is dead or alive. Thus, we say that the cat has a superposition of a probability of being alive and being dead. This is a basic approach to compare and contrast the states of the particles which make up the object and their states.
Remember the two electrons that were on the same orbital? For an atom to be stable and for the electrons to remain in that orbital in harmony, these two electrons must have different electron spin numbers, in other words their directions of their rotations must be opposite each other. If one spins upwards, the other has to spin downwards, and vice-versa. Their states of spin are bounded, and thus, they are subject to quantum entanglement.
For the Curious, This is What Goes Under the Hood
The simplified steps of the process of teleportation are as follows: First you have to have two entangled particles. Unfortunately, to teleport somewhere, you first have to take one of the entangled particles to the desired location (i.e the location to teleport the intended object to). So teleportation is a method to re-visit a place without any delay. The “bond” between entangled particles would remain even if they are many miles away. Scientists use this entangled pair to send another particle to another spot.
To do this we must involve the third particle (the one to send) in this entanglement. This process uses a complicated method that doesn’t involve any direct measurements; because if we measure the current state of one particle, we would break the entanglement by knowing both their states and wouldn’t be able to involve the third one into the entanglement. I know it sounds messy but bare with me a second. I won’t get into the math portion of it, but basically with “indirect questioning”, you put the third pair into a condition with one of the entangled ones that its state would be dependent on the entangled one. So now we have particle 3 sort of entangled to particle 1, and 1 was already originally entangled with 2; therefore, now particle 3 (the one to send) is entangled with number 2 (the one at the desired location.
After forming this relationship, now making particle 1’s state the opposite of 3’s, with the help of entanglement, all the states that particle 2 is in will be equal to particle 3’s. Voila, you have successfully copied a particle to the desired location. Because anything in the universe is basically combinations of the states of the particles that form that thing.
Now, we have made a measurement to establish the teleported object, we have transferred the states and created an exact copy at the desired location. Though making a measurement collapses the probabilities of the states since you now at that moment and it isn’t a probability anymore, thus the entanglement is disrupted. This will result in the original particle now having the most complex combination of states since the bond changed, therefore you will lose the original particle to send in the process. This way, quantum theory forbids cloning.
Although this discovery is such a critical one to achieve full teleportation, it is a difficult process that requires a lot of energy. Scientists are currently only able to send small particles like electrons, because an objects structure is much more complicated than a single particle since it is made up of billions of particles itself. So, unfortunately, there is a long way for the science world to cover before you can hop onto a tube and find yourself on Mars.
If you are interested, the following video explains the teleportation process much better and understandable than I did, with visual explanations: