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China's Quantum Radar Could Detect Stealth Planes, Missiles (popsci.com)

hackingbear shares a report from Popular Science: China Electronics Technology Group Corporation (CETC), China's foremost military electronics company, announced that its groundbreaking quantum radar has achieved capability of tracking high altitude objects, likely by increasing the coherence time entangled photons. CETC envisions that its quantum radar will be used in the stratosphere to track objects in "the upper atmosphere and beyond" (including space). Quantum can identify the position, radar cross section, speed, direction and even "observe" on the composition of the target such as differentiating between an actual nuclear warhead against inflatable decoys. [...] Importantly, attempts to spoof the quantum radar would be easily noticed since any attempt to alter or duplicate the entangled photons would be detected by the radar. The news is an important illustration of a larger trend of Chinese advancement in the new, crucial area of quantum research. Other notable projects in China's quantum technology include the Micius satellite, and advances by Alibaba and the Chinese University of Science and Technology in a world record of entangling 18 photons (a quantum supercomputer would require about 50 entangled photons), such that China arguably leads the world in quantum technologies.

8 of 194 comments (clear)

  1. We must stay competitive! by Anonymous Coward · · Score: 5, Funny

    We should implement Blockchain RADAR immediately as a response to this newfangled Quantum RADAR.

  2. Interferometry not quantum by Anonymous Coward · · Score: 5, Interesting

    They get two coherent photons, bounce one of a plane, receive it again and compare it to the original photon to see what's changed.

    Obviously it's not 'quantum entanglement' anything, because if it was, the BOUNCED PHOTON AND COMPARISON PHOTON WOULD ALSO CHANGE by fuzzy action at a distance.

    Sort of the exact opposite, since you need the original photon to not change to match the bounced photon. So if entanglement actually worked, this system wouldn't work.

    Sounds like Interferometry 101.

  3. Re:Relevancy by ShanghaiBill · · Score: 5, Insightful

    Why would China brag about this new advanced technology, telling the world that a "quantum radar" is indeed possible?

    China has no interest in an actual military confrontation. They want deference, so perception of strength is more important than reality, and bragging about new military tech makes sense.

  4. Re: Well, that's great, but by Anonymous Coward · · Score: 5, Insightful

    Why would you suspect that? Detection at an extreme early phase (think pre-launch even) allows for an unprecedented strategic window for countermeasures.

    If what you're saying is, "who cares if they can detect is at unprecedented distances and time-frames, our JASSM's are unstoppable" you're repeating an oft-made military blunder. Never fall back on your last presumed advantage when all others have been obviously stripped away. It's likely you simply aren't aware that your last advantage has (also) already been eliminated.

    If they've cracked quantum detection, don't be so confident about simple kinetic countermeasures -- let alone asymmetric tactics.

  5. Smells like BS by Anonymous Coward · · Score: 5, Insightful

    I am a researcher in the quantum communication area. Admittedly I can only judge by the poorly written Pop Science article, but the whole thing triggers my BS detector.

    "the coherence time entangled photons", "Quantum can identify..." - bad grammar is already a red flag.

    The whole "spoofing can be detected" sounds like someone made some confusion with QKD (quantum key distribution), a completely unrelated application of quantum technology.

    Finally, "a quantum supercomputer would require about 50 entangled photons"... Seriously, this is nonsense. I can't even.

  6. Re: Relevancy by Anonymous Coward · · Score: 5, Funny

    You never let your enemy know your position.

    Just tell them your velocity.

  7. Re: Well, that's great, but by Errol+backfiring · · Score: 5, Funny

    (think pre-launch even)

    You mean by following the enemy president's twitter account?

    --
    Nae king! Nae laird! Nae yurrupiean pressedent! We willna be fooled again!
  8. Re:How can we believe them? by rtb61 · · Score: 5, Interesting

    Obviously it is more about claiming developments in quantum technology, than stealth aircraft. To detect stealth aircraft all you need is high accuracy weather radar. You do not look for the aircraft, you look for it's impact on the atmosphere, pressure wave, changes in water density in the atmosphere and the exhaust itself. For searching this is far superior, because it presents a much, much larger target, a huge target. You don't see the plane but you see a very suspicious polluted cloud moving at hundreds of kilometre an hour, with out any regard to wind patterns and presenting a shock wave. How big a target, I'll bet it would be the best way to do over the horizon radar, not targeting the plane at all, just it's impact on the atmosphere, likely making over the horizon far easier and extend it's range far, far beyond line of site.

    So in reality stealthy planes are only stealthy if they don't move or start their engines and of course any plane is stealthy if it hides in a hanger. So why is everyone still paying for brand new stealthy, cough, cough, aircraft, the lust for profit and corruption. It's not like they don't know this and have not been aware of it for years, but when there is a buck in it for the military industrial complex, expect lies and the truth to be buried.

    --
    Chaos - everything, everywhere, everywhen