Back in February 2020, scientists at the US Department of Energy's Argonne National Laboratory and the University of Chicago discovered that they had achieved quantum entanglement – in which the behavior of a pair of two tiny particles becomes bound, so that their states are identical – this happened on an 83.7 km network with quantum loops in the suburbs of Chicago.
You might be wondering what all this fuss is about if you are not a scientist familiar with quantum mechanics – that is, with the behavior of matter and energy at the smallest scale of reality, which is especially different from the world that we can see around us.
The exploration of the researchers could be an important step in the development of a new, much more powerful version of the Internet in the next few decades. Instead of the bits that the modern network uses, which can only be expressed as 0 or 1, the future quantum Internet will use qubits of quantum information, which can take on an infinite number of values. (A qubit is a unit of information for a quantum computer.)
This would give the quantum internet more bandwidth, allowing it to connect ultra-powerful quantum computers and other devices and run applications that are simply not possible with the internet we have.
“The Quantum Internet will become a platform for the quantum ecosystem in which computers, networks and sensors exchange information in a fundamentally new way, in which sensing, communication and computation literally work together as one,” explains David Aushalom, professor of spintronics and quantum information at the School. Molecular Engineering by Pritzker at the University of Chicago and a senior fellow at Argonne, who led the quantum loop project.
What is the Quantum Internet?
So why do we need him and what does he do? For starters, the quantum internet is not a replacement for the regular internet that we now have. Rather, it is an addition to it. He could take care of some of the problems that are interfering with the current internet. For example, the quantum internet will provide greater protection against hackers and cybercriminals. Right now, if Alice in New York sends a message to Bob in California over the Internet, that message travels more or less in a straight line from coast to coast. Along the way, the signals that carry the message are degraded; repeaters read signals, amplify and correct errors. But this process allows hackers to 'crack' and intercept the message.
Quantum messaging doesn't have this problem. Quantum networks use light photon particles to send messages that are immune to cyberattacks. Instead of encrypting a message using mathematical complexity, we will rely on the special rules of quantum physics, according to Ray Newell, a researcher at Los Alamos National Laboratory. With quantum information, 'you cannot copy or split it, and you cannot even look at it without changing it.' In fact, simply trying to intercept the message destroys the message, as Wired log notes. This would make everything much more secure than what is available today.
“The easiest way to understand the concept of the quantum internet is with the concept of quantum teleportation,” says Sumit Khatri, a researcher at Louisiana State University at Baton Rouge. He and his colleagues wrote an article about the possibility of a space-based quantum Internet, in which satellites will continuously broadcast entangled photons to the Earth's surface, as described in the Technology Overview article.
“Quantum teleportation is not like what the mind of a non-scientist might come up with in terms of what they see in sci-fi movies,” says Khatri. 'In quantum teleportation, two people who want to communicate share a pair of quantum particles that are entangled. Then, through a series of operations, the sender can send any quantum information to the receiver (although this cannot be done faster than the speed of light). This aggregate of common entanglements between couples of people around the world essentially constitutes the quantum Internet. The main research question is how best to distribute these entangled pairs among people distributed around the world. '
Once this can be done on a large scale, the quantum Internet will be so amazingly fast that the remote clocks will be synchronized about a thousand times more accurately than the best atomic clocks available today, according to Cosmos magazine. This would make GPS navigation much more accurate than it is today, and would display the Earth's gravitational field in such detail that scientists can notice the pulsation of gravitational waves. It could also allow photons to teleport from distant visible light telescopes across the earth and link them into a giant virtual observatory.
“You could potentially see planets around other stars,” says Nicholas Peters, team leader for quantum information science at Oak Ridge National Laboratory.
Problems of building a quantum Internet.
But before any of this can happen, researchers must figure out how to build a quantum Internet, and given the weird nature of quantum mechanics, it won't be easy. “In the classical world, you can encode information and store it, and it doesn't get destroyed,” Peters says. “In the quantum world, you code information, and it starts decaying almost immediately.”
Another problem is that since the amount of energy that corresponds to quantum information is really small, it is difficult to keep it from interacting with the outside world. Today, “in many cases, quantum systems only work at very low temperatures,” Newell says. “Another alternative is to work in a vacuum.”
Newell says that in order to create a quantum internet function, we need sorts of hardware that hasn't been developed yet. Therefore, it is difficult to say exactly when the quantum Internet will be launched, although some scientists suggest that this could happen as early as 2030.
