At first an unassuming net-invader, “quantum” has certainly become one of the buzzwords of the 21 st century. However, it’s also one of the most obscure terms; maybe even the one most people use without any clear understanding. That’s why we decided to clear some things up. And after our introduction to quantum computing (QC) and our 2018 update (check them out), we’ll now move on to something even more interesting and less discussed – quantum internet.
In theory, Quantum Internet (QI) is a network which allows for communication between physically separated quantum computers. And obviously, QI is an important element of QC. But, is it a plausible and viable concept?
Let’s find out together.
The Basics of Quantum Computing
In physics, the word “quantum” refers
to “the minimum amount of any physical entity involved in an interaction.” Though theoretical studies on quanta and quanta-related events go a long way back, it seems that the most interesting practical implications are yet to be discovered.
But we’re getting ahead of ourselves.
Qubits, Quantum Superposition and Quantum Entanglement
The key to understanding the idea behind QC is figuring out how quantum particles behave. Because unlike in classical computing – where information is represented by bits – the basic unit in QC is quantum bit (or qubit for short).
And the interesting thing about qubits is that they can be in two different states at the same time. This is called the quantum superposition principle. Moreover, it turns out that this principle closely related to a phenomenon called quantum entanglement. Loosely speaking, entanglement means that two (or more) physically separated quantum particles act as if they are one and the same.
And it’s one thing when the two states of a single quantum particle can’t be described separately, and a completely another when this is true of two different particles. Because, when we say “entangled” – we do mean “entangled”! In other words, when you do something to one particle, its entangled partner gets changed as well.
But, you know what they say: less physics, more magic!
You’ve read it right!
Although it’s not physical – and not even a form of transportation – quantum teleportation (QT) is something which is as SF as it sounds.
QT is a process by which, with the help of quantum entanglement, quantum information can be transmitted from one location to another.
Bear with us for a moment!
Two entangled particles/systems act in a way which produces modifications in the second particle/system, even though the first one is the only one actually affected. Now take into consideration the fact that the distance between the entangled particles doesn’t matter at all! In other words, if you have one particle in Africa and another one in Alaska, you will be able to send information between them by modifying only one of the them!
Back to Quantum Internet
Now, back to QI.
Quantum transportation opens up possibilities for a completely new type of networks. Namely, if you can share the exact state of a qubit between locations, without moving anything physically, you don’t even need optical fibres anymore!
The phenomenon of quantum entanglement was first proven in 2015, by a team led by Ronald Hanson, a professor from Delft University of Technology in the Netherlands. Hanson and his team linked two particles which were 1.3 km away from each other. But, let’s give Hanson some space
“Quantum teleportation is the most fundamental operation that can be done on the quantum internet. So, to get entanglement distributed over long distances, you are actually teleporting the entanglement from one node to the other. In a classical network, you send your data package, and there is an address contained in that, and the router will read off that information and send it on to the next node. We don't want to do that with these quantum signals. We want to send these quantum signals by teleportation so they don't have to go through the (optical) fibre; they disappear on one side and reappear on the other.”
But, hold your horses: it’s not like you’ll be able to order your QI package tomorrow! There are still certain problems to be addressed before QI becomes reality. And the biggest one is scale-related. After all, what works at microscopic – may not work as well at macrolevel:
“The vast majority of phenomena and events that occur in our daily lives can be accounted for by the laws of physics established by Isaac Newton, but the microscopic world obeys the rules of quantum mechanics, which are so strange that they can seem counter-intuitive,”
says Hendrik Ulbricht, a professor of the University of Southampton, one of the UK universities which will conduct an experiment to test the limits of quantum theory
Now, if it turns out that the same laws of quantum mechanics can be applied to macroscopic objects, it will mean that we can make much smaller computer chips and start using quantum communication for creating complex quantum networks.
Main Applications of QI
Though somewhat limitedly, some of the benefits of quantum computing (such as quantum encryption) are already taken use of. There’s a long way to go at the present moment, and it’s difficult to make more accurate predictions. But, let’s try and see to what extent will time vindicate our guesses.
Secure Data Transfer
The phenomenon of quantum entanglement implies not only seemingly unlimited possibilities of sending information from one computer to another, but also encrypting that isn’t even possible in classical networks.
Quantum cryptography is based around the idea that each quantum signal contains a cryptographic key shared between the ends of the quantum channel. And if someone tries to intrude, this key gets destroyed.
As of now, quantum cryptography
isn’t seen as a substitute for traditional cryptography, but, rather, as an additional option for secure data transfer. However, as computational speeds increase and artificial intelligence advances, the need for quantum cryptography may drastically increase
For the first few “computer decades”, it was computing power – and not the lack of knowledge or modern algorithms – that was the main obstacle for faster data processing. However, processors got better, and for a while, it seemed that there were no more obstacles. But, nowadays classical processors may be as good as they will be
, and even supercomputers
don’t work as fast as we need them to.
And this is where quantum computing comes in. It’s much, much faster.
You can already use IBM quantum cloud software to run math-heavy algorithms. (Consider that 30-qubit quantum computer equals the power of 10-teraflops conventional computer in processing power, and IBM’s platform lets you use a 20-qubit processor). Google never stays behind, and is currently focusing on applying quantum computing to solve Artificial Intelligence and Machine Learning problems
Combining classical and quantum computers in a cloud opens up completely new possibilities for managing data. The thing is that the most important algorithms nowadays are based on fast database searches, and quantum parallelism can drastically boost their speed. Moreover, it’s already accessible within quantum cloud software.
Obviously, QI promises a world of wonders. However, it’d be wrong to expect that it will replace classical internet. Scientists, in fact, are much more focused on upgrading it. Consequently, researchers at many universities are currently working on the creation of chips which will make possible to connect a traditional computer to a quantum network.
Just imagine the possibilities!
It’s difficult to predict the future of quantum technology. But, as we see it, secure data transfer, advanced problem-solving and data manipulations are three spheres where quantum internet may have more immediate effects. But, again, things change fast and there may be much more to come!
Even so, we’ll hazard a guess and say that even a decade from now, most likely we will still be using the same Internet we use now. However, we will also be able to use parallel quantum computing for numerous more specific tasks.