It may be that the first time you heard about quantum computers, about their super processing power , you thought that it could be the new equipment that you installed in your office. However, nothing could be further from the truth. Quantum computers have nothing to do with the traditional computers that we had known until now and whose use, today, so many people have fully incorporated into their daily lives.
Our current computers work thanks to what is known as bits, a flow of electrical or optimal pulses that are organized in series composed with a linear sequence of 0s and 1s combined in different ways. Through this binary language , everything we have on our computer has been shaped: from the most complicated program to a simple Facebook post.
However, quantum computers appear in the universe of quantum mechanics which, compared to linearity, assumes that a particle can be in two different states at the same time. Something like Schrödinger’s cat , which could be either dead or alive.
Quantum computers, on the other hand, use qubits , subatomic particles like electrons or photons. Strings of qubits can provide much more processing power than the same number of binary bits. And the goal is to isolate the qubits in a controlled quantum state. In addition, they can represent many possible combinations of 1 and 0 at the same time, which is called “overlapping .” The “entanglement”, another of its specific characteristics, means that the two members of a pair of qubits exist in a single quantum state. so changing the state of one of the qubits will instantly change the state of the other in a predictable way, even if they are separated by very long distances. Both characteristics allow to exponentially multiply the computing power of quantum computers, but, in turn, it is much easier for it to make mistakes when doing so.
This is due to what is known as “decoherence” , since the quantum state is incredibly fragile and any variation in temperature or noise can prevent quantum computers from doing their jobs correctly. This is also the reason why laboratories keep them at very low refrigeration temperatures, another reason why it would be a bit difficult to put one in our homes.
The interaction of qubits with their environment in a way that causes their quantum behavior to decay and eventually disappear is called “decoherence .” Its quantum state is extremely fragile. The slightest vibration or change in temperature – disturbances known as “noise” in quantum parlance – can cause them to fall out of the superposition before their work is done correctly. That’s why researchers do their best to protect qubits from the outside world in those supercooled refrigerators and vacuum chambers .
So it seems that, for the moment, we will have to wait for large companies such as Google or IBM to continue developing and researching quantum computers before considering replacing our notebook or laptop with them. Meanwhile, pharmaceutical companies, automobile companies and air transport companies are making use of this tool, to research new drugs or to carry out simulations of the chemical reactions that take place in car batteries. Furthermore, in the future what is aspired to is “quantum supremacy” , the point at which a quantum computer can complete a mathematical calculation that is demonstrably beyond the reach of even the most powerful supercomputer.
