According to New Scientist, researchers at Shanghai Jiao Tong University led by Xianfeng Chen have built one of the most complex quantum networks ever created, connecting 18 users through quantum entanglement. The team started with two separate 10-node networks and sacrificed one node from each to fuse them into a single 18-node network where every pair can communicate securely. This breakthrough uses a process called entanglement swapping to link photons across different networks, creating what the researchers call a “crucial capability” for building large-scale quantum internet. However, other quantum experts remain skeptical about whether this approach can realistically scale to global networks given current technical limitations and costs.
Impressive but impractical?
Here’s the thing about quantum networking: it’s ridiculously hard compared to classical networks. When you’re dealing with individual photons and quantum states that collapse if you even look at them wrong, everything becomes exponentially more complex. What Chen’s team achieved is genuinely impressive from a pure research perspective – getting 18 nodes all entangled and communicating is no small feat.
But Robert Young at Lancaster University isn’t convinced this is the path forward. He calls it a “phenomenal technical achievement” but questions whether something this complex and expensive could ever scale to a global quantum internet. Basically, we’re talking about cutting-edge labs with massive resources versus something that would need to work reliably in the real world. Young’s frustration is palpable – he says the approach is “so far from practical” and “so far from anything that could be implemented in the real world.”
The elephant in the room
Here’s the biggest challenge this research doesn’t solve: quantum repeaters. In classical internet, we can boost signals along fiber optic cables using repeaters. But with quantum information, you can’t just read and retransmit because measurement destroys the quantum state. Photons get lost over distance, and without working quantum repeaters, we’re limited to relatively short-range networks.
Young puts it bluntly: “Practically, building a quantum network, we know we’re really going to need some form of quantum repeater.” This network demonstration doesn’t address that fundamental limitation. So while connecting 18 users in a lab is cool, scaling to global distances? That’s a whole different ball game.
Two paths forward
What’s interesting is how this fits into the broader quantum communications landscape. Siddarth Joshi at University of Bristol explains there are basically two competing approaches right now. Some researchers are focused on sending quantum information over increasingly longer distances – we’re talking satellite-to-ground connections here. Others, like Chen’s team, are working on networking many devices at shorter ranges.
Joshi gives credit where it’s due: “What they have done is they have created a scheme where you can do the swapping between the networks in a bit more of a convenient way.” Both approaches matter, but they’re solving different parts of the puzzle. The question is which one will prove more practical when we’re ready to build something at scale.
So where does this leave us?
Look, quantum internet isn’t happening tomorrow regardless of which approach wins. What this research shows is that we’re making progress on the networking side – being able to fuse quantum networks together is definitely a step forward. The published paper in Nature Photonics represents real scientific advancement.
But the skepticism from other experts highlights a crucial reality: technical achievements in labs don’t always translate to practical solutions. We’re still years, probably decades, away from anything resembling a global quantum internet. The fundamental physics challenges around quantum repeaters and scaling remain enormous. So while this is exciting research, don’t cancel your current internet provider just yet.
