Entangled by Quantum Supremacy

[Dr Wu]

The many online articles about the future security issues posed by quantum supremacy — at least those pitched at the interested layperson (like myself) — tend for quite understandable reasons to focus on the outcomes that QS will have on today’s digital-based security systems. . . not as they might manifest in the slightly more distant future.

So assuming in such a futuristic context that quantum supremacy is now globally supreme, does this mean then that the world at large, that’s to say everyone from corporate CEOs to your local candlestick maker, will be safe from online hackers? In other words, will full-on quantum cryptography spell the end, not only of cryptanalysis as a profession, but also doom the entire global intelligence-gathering/cyber-monitoring defence industry, with government agencies like the NSA and GCHQ consigned to the dustbin of history?

If so, this at first glance could be both a Golden Age and a Dark One; golden in that all personal communications will be safe from all such online attacks; dark because the means to monitor terrorists, criminals and rogue state operatives by remote means are now essentially scuppered. Another way to look at it is that QS returns/regresses the modern world back to a kind of pre-Marconi state of innocence, one that a Victorian letter writer or Pony Express rider would have recognised? Or is this being too simplistic?

One thing is for sure: it’s getting to be mighty hard to read an Earth-based, techno-driven SF story set in the nearish future that doesn’t (by whatever sleight-of-hand means) take account of the above outline. Even offworld-based SF that includes space communications isn’t entirely free of this restriction.

A personal note: as someone penning such a story, it’s getting to the point that this endlessly put-off issue has left a bad smell festering in the plotting department. The only recourse is to assume that quantum supremacy means what it says; that it’s re-established communications privacy at all levels, so learn to live with it. The bad smell still lingers, though. Hence this plea for some clarification.

Thanks for reading this post.

 

[.Scott]

I prefer the phrase "Quantum Advantage". "Quantum Supremacy" is a bit too romantic for my blood - and it suggests that quantum computing will eventually replace and obsolete regular digital computing. It will not. In fact, you need digital computers to operate qubit processors.

There are two cryptographic algorithms that would become obsolete if quantum computers were able to effectively entangle hundreds of qubits into a single state. Those algorithms are RSA and elliptical curve codes.
Groups such as ETSI are assisting in attempts to transition to cryptographic codes that can be proven to be quantum safe.

There is a quantum-based method for transmitting information that is protected by statistics and the laws of Physics from being intercepted - and that is probably what you are referencing in your post.
Here is an article describing that technique.

 

[Dr Wu]

Thanks for your helpful comments - and the links too. Interesting reading. Your statement about the need for digital computers to operate qubit processors intrigued me somewhat.

Another thought: would a quantized signal, beamed, for example, via a laser, risk becoming corrupted by the medium through which it's being transmitted, namely the atmosphere itself? Might the same problem also occur with space communications, here space weather coming in the form of the solar wind, cosmic rays etc? I should imagine that the shielding supplied by a cabled connection would nullify this problem, assuming it's a problem in the first place, of course. Just a thought.

Yes, "quantum supremacy" does sound a tad overblown.

 

[.Scott]

Another thought: would a quantized signal, beamed, for example, via a laser, risk becoming corrupted by the medium through which it's being transmitted, namely the atmosphere itself? Might the same problem also occur with space communications, here space weather coming in the form of the solar wind, cosmic rays etc?

The same methods that are described in the second article for detecting internal errors could also be used to detect transmission issues. There are always transmission "risks". The transmission "risk" that is most important in these quantum systems is the risk of the information being intercepted. Entanglement can keep that risk at bay.

 

[Dr Wu]

Yes, I read the article the first time, but clearly missed the connection.

More generally speaking, it's surprising that so little about QA appears to have reached the mainstream print media. There's no end of books published on the subject on black holes, for instance; a fair number too about AI, and its societal implications. Even so, the quantization of the electronic media, and the huge impact it's likely to have upon society at large, almost seems to be - to borrow Ray Kurzweil's term - a "singularity" in its own right. Apart from a scattering of technical papers on the subject, the eyes-wide-shut attitude adopted thus far by the major publishing houses is startling. Quite remarkable, in fact.

Just giving my ten cents worth.