The internet has gone from being a curiosity, to something that has profoundly changed our way of life, in the space only about 25 years. But what if we could take a gigantic leap, like a Quantum one. And yes, I know an actual quantum leap is very small, but bear with me here because this is actually pretty cool.
Quantum internet, which is currently being worked on by researchers around the globe, could make our current internet look primitive. And unlike pipe dreams like cold fusion or faster than light travel, you could at least be partially available, within our lifetimes. But why would we want that? To find out, we spoke to Chad Orzel, so we'd like to thank him for his insight.
Well, unlike the current internet that works with standard bits, ones and zeros, the quantum internet would use quantum bits or qubits, which can represent both a zero and a one at the same time in superposition. This means complex operations could be done in fewer steps, than a current computer would need, making a quantum internet much more efficient, for some types of applications.
For example, if we're using qubits, large amounts of information could be sorted through much more quickly, without it being indexed first. A quantum network would also be superior in some ways due to a concept called quantum entanglement. This is a weird counterintuitive phenomenon, but we'll do our best to explain how it works.
Basically, if you change the properties of one particle, the properties of a second linked particle changes instantaneously, even if it's really far away, to the bizarre nature of quantum physics. However, there's a common misconception that this means that we can transmit information instantaneously, as in faster than light. Unfortunately, this isn't the case for a few reasons.
One, quantum entanglement requires both the sender and receiver to measure their quantum particle, which actually changes it. And then compare results, to see if they're correlated, in order for useful information to pass. And that has to be done at, well below light speed.
Two, quantum networking requires quite a bit of overhead, to ensure the information could be carried properly, as the whole process is relatively fragile. So really it's not about getting faster in the sense that a cable connection is faster than a dial-up one, rather, it's about making certain kinds of applications more efficient, kind of like how current super computers and graphics cards are parallelized. And also about security. Remember how we said measuring a quantum particle changes it? This means that, trying to look at something like a quantum encryption key, would destroy it before an attacker could actually use it, making quantum networks, far more secure than what we have today.
But hold on, how do you even encode a qubit? Well, one method scientists are looking at is shining lasers on a single ion, in a certain way that encodes quantum information. The ion then spits out a photon, that has the same information. So you can say, the ion and the photon are entangled. When that photon meets a photon from another ion, the two ions then become entangled through the bizarre physics that govern quantum mechanics.
Now all of this sounds cool, but quantum networks work best in relatively cold, temperature controlled environments. So scientists have had to overcome the major barrier, of making them reliable in real world conditions.
Additionally, because quantum networking would still rely on photon transfer, light attenuation is also something to consider, just like with current fiber optic networks. But in spite of these challenges, a team in China, has gotten a quantum entanglement connection, to work over a distance of 745 miles. Long distance transmission would required repeaters, but appears that we aren't too far away from a proof of concept. In fact, one of the leading researchers on China's quantum project, thinks we'll have quantum internet in some form by the year 2030. Of course, an early version of the quantum internet would almost certainly be an add-on to the current internet, instead of a total replacement.
If you're expecting mainstream gadgets like smartphones and PCs, that support quantum transmissions natively, we probably won't see that in our lifetimes. But it'll be interesting to see, if we start getting benefits from quantum internet in the next couple of decades. Maybe it'll somehow make the computer network at the DMV work a little faster for example, but, I wouldn't hold my breath.