Yesterday we brought you an article about the quantum internet. Since this is one possible future, it’s definitely good to know how this internet actually works. So let’s take a look at how the quantum internet works.
The “normal” internet
The Internet as we know it today can be imagined as two computers connected by cable, which soon have access from one to the other. So data can be transferred from the first computer to the second and vice versa. The Internet is a huge number of computers that are connected to each other. At the same time, there are different rules and hierarchies for proper functioning in this network. But the bottom line is that we end up with a big pile of interconnected computers. This is how we can imagine the Internet working today.
The data from these computers can be transmitted by cable, air or light beams (fibre optic cable) and is transmitted in so-called packets, which break the information down into individual “packages”. This data is always sent by one PC and received and reconstructed by another.
The quantum internet would work in much the same way, again transferring data from one computer to another. This time, however, it would not use data packets, but photons that would be entangled. Entanglement is a special quantum mechanical property that allows individual photons to “think” as one mind. When you make a change on one side, the other side immediately knows about the change. But if you need to send the information over a long distance, you’ll need a quantum repeater along the way.
A quantum repeater
First, the photons need to be created and entangled. Then you send one of the pair to the measuring device and the other to the end user. Once the two parts of the pair arrive together, they exchange the stored information and because of this, they “alarm” the other part of the pair of the change and overwrite the memory.
Such an Internet could create secure connections between users. Much more secure than the ones we are used to now. It could also help science, protect sensitive information, and help quantum computing reach a whole new level. If the quantum internet were to take off, it would affect all the areas where the internet now reaches, including cryptocurrencies, which could benefit from quantum algorithms.