Advance opens door for secure quantum applications without specialized infrastructure
#Hey Kids! Guess which word is getting shoehorned into EVERY technology discussion in 2025 until it becomes meaningless?
So theyâve shown they can send light over a cable designed to transfer light.
The impressive thing is of course managing to get one specific photon to one specific location. Still, what benefits does that have over the standard encoding?
I guess this technique might have a lower error rate and higher distance, because itâs binary by nature with no quantization needed. But you donât need the quantum entanglement part at all for this.
Edit: Reading is hard! This is indeed exciting for security. I wonder how it fairs against a very powerful MitM though.
Only limited by the speed of light,
What exactly do you think the normal ip data is limited by on the same optical cable?
I thought we were talking about quantum entaglement and spooky action at a distance, which is famously not limited by the speed of light?
Am I missing something obvious?
The article starts by doing the âquantumâ thing that really irks me, where they use confusing terminology to make it sound like âFTL communicationâ without actually saying it. This is garbage that doesnât actually matter to the article.
Basically, they found a way to send quantum entangled photons (which exist in a very delicate unobserved state) through existing fiber optic infrastructure without interfering with the standard internet information already travelling through the fiber. A lot of the difficulty with this is due to signal noise that needs to be filtered out. This will be useful communicating quantum measurements over long distances.
They then go on to describe what sounds like
-
transmitting a single specific photon through âthe internetâ, implying start-to-finish with routing (not possible without special infrastructure)
-
Use that photon to then send information instantly by manipulating its entangled sibling (also not possible)
So yeah this article is a crock of shit.
This is a cool progress forward.
TLDR; Researchers used a 30km optical fiber. They found a wavelength that was off-to-the-side that would mean the quantum entangled photons could ride in the same fiber without interfering (or being interfered with) the classical fiber optic communications. One current shortcoming for scaling this up is that the quantum photons would not survive optical repeaters commonly used for extremely long distant fiber runs. That doesnât take away from the success of their research, just puts it in perspective for the next researchers to tackle at some point in the future.
Is the reason (Im assuming you ment) it canât survive a repeater survive a repeater because it collects and recreates the particle? These cables are ment for logical data transport.
Yes. Keep in mind nothing in the article talks about the fiber repeater. That is my addition with some knowledge of telecommunications infrastructure. Because fiber optic cable isnât perfect, there is light loss over distance. Different grades of fiber have different levels of loss across distance. An example of high end fiber would be ZBLAN. There is experimental level manufacturing (successful in small quantities already) of producing ZBLAN fiber in space to improve the fiber quality, but that makes it much more expensive. Once the limits of the fiber are reached a telecommunications provider can place a fiber repeater to double the length by intercepting the light (signal) and reproducing it (blinking new laser light) into the next segment of fiber.
However, these repeaters create NEW light, and that would mean the quantum information is not carried over in present day fiber repeaters. Even measuring the entangled photon to recreate it would break the quantum state of the entangled photon at the source, so current means canât be used as a repeater for quantum data.
