China Says It Has Developed a Quantum Radar That Can See Stealth Aircraft (digitaltrends.com)

An anonymous reader quotes a report from Digital Trends: At a recent air show in the city of Zhuhai, state-owned Chinese defense giant China Electronics Technology Group Corporation displayed what it claims to be a quantum radar that's able to detect even the stealthiest of stealth aircraft. The company claims to have been working on the technology for years, and to have tested it for the first time in 2015. In principle, a quantum radar functions like a regular radar -- only that instead of sending out a single beam of electromagnetic energy, it uses two split streams of entangled photons. Only one of these beams is sent out, but due to a quirk of quantum physics both streams will display the same changes, despite being potentially miles apart. As a result, by looking at the stream which remains back home it's possible to work out what has happened to the other beam. According to a brochure from the China Electronics Technology Group Corporation, the new quantum radar could "solve the traditional bottleneck [of] detection of low observable target detection, survival under electronic warfare conditions, [and] platform load limitations."

Comments

Another claim

[Actually, I do RTFA]

They had a similar story last year, and the year before. It's not true. If it was, the last thing they would do is tell everyone that they can see stealth plans (or at least how they did it so it could be duplicated/nullified.) But it's not true. It's designed to impress someone, I'm not sure who.

Re: Riiiight

[Anonymous Coward]

Stealth planes were operational before announcement

Here's a thought

[nehumanuscrede]

If China is claiming the technology to " see " stealth aircraft is now a reality, why are they still spending big $$$$ on building stealth aircraft ?

China is fixated on image. They took that whole " fake it till you make it " saying to heart and desperately wants the entire planet to believe they are the most amazing, powerful and capable country in history.

It should be noted the term " Paper Tiger " originated in China. They should be all too familiar with what it means since they are basically the very definition of the word.

Re:Riiiight

[ShanghaiBill]

If a country believes that war is likely or inevitable, it is better to hide their capability so enemies are unprepared.

If a country is primarily interested in deterring war, it is better to advertise new capabilities so enemies are intimidated.

Historically, America has tended to follow the first strategy, and keeps new developments secret.

Most of America's adversaries have tended to follow the second strategy. During the Cold War, Russia often tried to look stronger than they really were. Today, China does the same.

Re:Bonus: it disproved Bell's theorem!

[Baloroth]

Harnessing that fact to transmit classical information faster than light is a completely separate question. But nobody is claiming that is happening here.

That is exactly what the summary is claiming is happening:

As a result, by looking at the stream which remains back home it's possible to work out what has happened to the other beam.

That is precisely what you cannot do: examining the photons you have doesn't tell you any information about what has happened to the photons you sent out, the only "information" it gives you is (basically) the what the state the photons you sent out will be if they haven't interacted with anything (you don't, however, know if they have interacted with something or not). Since the point of radar is to interact with whatever you're looking for, that makes it rather pointless.

Note that a "quantum radar" could maybe improve on classical radars by comparing reflected photons to give you more information about what exactly reflected them, but it's still only useful if you get some of the photons you send out back. Even then I doubt you could actually make such a system (I'm not entirely sure it's physically or even theoretically possible). I am sure, however, the Chinese don't have such a system: they would never publicly disclose it if they did. The only reason to brag about it's existence is to either convince other countries to waste time trying to replicate it, or to convince them their stealth fighters will be useless against the Chinese. Either way, it's a purely psychological move.