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The Great Quantum Leap

China’s new satellite looks like a game-changer


“Hack-proof” is the term being thrown around in regard to China’s new satellite, launched from Gansu on the August 16, and those with a passing knowledge of quantum entanglement understand why. Be it carrier pigeon, post, radio transmission, or Internet, every form of communication has been vulnerable to interception, but in the case of quantum entanglement this isn’t physically possible.

Essentially, through a process of scientific chicanery, two photons become “entangled” then what affects one, affects the other (there’s a whole lot more to it than that of course, but this is the basic gist).

The process of looking at the photons to see what is happening to their bizarro-twin is called “quantum communication”.

This allows for near-instantaneous communications via photons “encoded” with information(the photons react instantly but there has to be communication to correct the particle’s spin and make sense of it, so it’s effectively back to a speed of light maximum). Scientists at Qinghai lake successfully conducted this process via two stations that were separated by 97 kilometers in 2012, by firing photons between relay stations inside a laser at night.

But things really get weird when this process is observed: it can’t be.

The process of observation, be it visual or recorded by other means, changes the results. There are various theories as to why this may be the case, and physicists love nothing more than arguing about them (with a satellite now in the equation, astrophysicists will probably get in on the action much more), but by and large it’s a black box filled with mystery.

But this makes it really useful for communications—if anyone else has seen it, recorded it, intercepted it in any way, the encoded data will be scrambled. Only messages that were not intercepted will make any sense (but will still require people at both ends to communicate after a message is sent via other less secure channels, because they have to input more data according to what the other entangled photon is doing at the same time. Think of it as a message on a ball thrown to you that’s still spinning, but you have to ask the pitcher how to get it to stop spinning long enough to read what’s on it. The ball message is secure, the shouted instructions to read it might not be).

The satellite project has been dubbed “Quantum Experiments at Space Scale”, or QUESS. It’s not going to be easy though, as with all new technologies, there are a lot of factors that need to be considered and quantum particles are particularly mischievous, defying Einstein’s predictions at every turn and living up to the moniker “spooky action at a distance”.

So what is the potential of this project?

Well, first and foremost, scientists need to figure out how all these scenarios are affected by large distances and space. We don’t really have a firm idea of how well these things are going to work on this scale, but there really is only one way to find out for sure—launch a satellite into space, hence the QUESS quest. Plenty of scientists are going to eagerly await the results of each test, and no doubt one of the first big issues to resolve will be whether this information is shared openly and to what extent.

The project has a lot of promise though—a handful of the world’s top scientists, seemingly frustrated at roadblocks or funding limitations on quantum research overseas, have come to China to get in on this exciting project.

Provided they can surmount the many obstacles, the main advantages would be secure communications and a deeper understanding of future applications of this science, which at this point are difficult to really comprehend. Quantum computing is another contentious area of research, with supporters claiming it could revolutionize computing beyond all current frameworks, while others say it’s still unproven in a practical sense.

In any case, buckle up. Things are about to get spooky.


Cover image from Sohu

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