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Royal Navy says quantum navigation test a success

thequantuminsider.com

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Re: Royal Navy says quantum navigation test a success

#31

Post by andromeduck »

Looks like what's happening is they've found a way to use BSEs [1] to measure small variations in the earth's gravity caused by undersea terrain, probably so that they can then use existing satelite measured data [2], to recover absolute position via Terrain Contour Matching [3] like a gulf war tomahawk missle.

Edit: Seems like there's another company that's doing the same thing [4] with BSEs [5].

[1] https://physics.stackexchange.com/questions/570707/why-is-ru...

[2] https://en.wikipedia.org/wiki/TERCOM

[3] https://earthobservatory.nasa.gov/images/87189/seafloor-feat...

[4] https://www.youtube.com/watch?v=9ZiUfw6ftq4

[5] https://www.youtube.com/watch?v=X7Y7MikUS4M

Re: Royal Navy says quantum navigation test a success

#32

Post by etrautmann »

rogers18445 wrote: post #29
jchallis wrote: post #13

This is the most obvious practical application of my PhD topic. A Bose Einstein Condensate is an extremely sensitive detector of gravity- a nuclear submarine could use it to make an ultra-accurate map of the world based on variations in the gravitational constant g. This would remove one of the primary reasons subs need to surface , in order to GPS lock. It’s a naval chart that would not require surfacing. A French p…

What would you do with the g measurement to get your location? Can g deltas be matched to sea floor contour maps? Otherwise it seems like subs would have to be following g-mapped routes.

With a highly detailed map, it becomes a statistical fitting problem, to locate yourself based on an estimate of position history using intertidal measurements and your time history of gravitational measurements, starting from an initial position estimate. I would imagine this could be quite accurate.

Re: Royal Navy says quantum navigation test a success

#33

Post by bottom999mottob »

HyperSane wrote: post #28
kebman wrote: post #24

A friend of mine got PTSD from piloting huge nuclear subs in subsea ravines with a clearing of only one inch on each side of the sub. One wrong move, and the entire crew is gone. He also had to do this in conditions similar to surface storms. Looks like autonomous or automatic systems may be developed for those kinds of manoeuvres now, if it is truly that precise. Seems like a huge leap in navigational systems.

There is no way that subs can be controlled accurately enough to do that.

There is no way anyone would hyperbolize the experience of their friend squeezing a submarine through ravines on the internet.

Re: Royal Navy says quantum navigation test a success

#34

Post by UberFly »

bottom999mottob wrote: post #33
HyperSane wrote: post #28

Earlier quoted context omitted.

There is no way that subs can be controlled accurately enough to do that.

There is no way anyone would hyperbolize the experience of their friend squeezing a submarine through ravines on the internet.

Squeezing submarines through internet ravines sounds really interesting. Go on.

Re: Royal Navy says quantum navigation test a success

#35

Post by buildbot »

HyperSane wrote: post #27
rocqua wrote: post #25

I'm surprised we don't see more military research for SAT-NAV alternatives. In any big conflict SAT-NAV is trivial to turn off. If you can still position yourself and your enemy can't, that is an enormous advantage in targeting, logistics, coordination, and situational awareness. Seems like a no-brainer.

The US military is working on a device that can use stars to determine location even during the day.

Couldn’t that be just celestial navigation with a very specific notch filter for starlight wavelengths? So you can see stars in daylight?

Re: Royal Navy says quantum navigation test a success

#36

Post by gnfargbl »

The Imperial College researcher who builds these things describes his research here: https://www.imperial.ac.uk/centre-for-cold-matter/research/q...

The page claims that this device attempts to measure acceleration accurately enough that position can be determined (by integrating over time, twice).

Re: Royal Navy says quantum navigation test a success

#37

Post by multjoy »

HyperSane wrote: post #26
themodelplumber wrote: post #19

Earlier quoted context omitted.

Fascinating. Q for you since you are so clued in. I am a ham radio operator and was thinking about novel forms of signal propagation. I landed on the idea of gravitons. Could gravitonic signal propagation be done somehow? While researching, I keep coming across familiar terms I know from radio land. Just curious if the fields here could be harnessed for communication. Thanks.

Gravity waves are way too hard to detect and generate to be used for communication. The waves we can just barely detect too 8 solar masses worth of energy to generate.

And people complained about next door's aerial farm!

Re: Royal Navy says quantum navigation test a success

#38

Post by sakras »

kebman wrote: post #30
rocqua wrote: post #25

I'm surprised we don't see more military research for SAT-NAV alternatives. In any big conflict SAT-NAV is trivial to turn off. If you can still position yourself and your enemy can't, that is an enormous advantage in targeting, logistics, coordination, and situational awareness. Seems like a no-brainer.

You're probably surprised that you don't see it, because it's top secret. Here's an example of something you don't hear about: AI Assisted Battlefield Tactics. While I've never heard of it (certainly not in the press), I simply assume that they're doing research on it. I base this assumption on the AlphaStar AI from DeepMind that would completely pawn Grand Masters in the game of StarCraft 2. While AlphaStar is obvio…

AlphaStar hardly pawned GMs in any meaningful way. It mainly won on mechanics, even when Deepmind tried to nerf its mechanics. Probably the most important thing is that the “200 APM limit” is way higher than any human can do, because it made use of each one of its actions. Humans can reach 400+ APM by spamming, but their EPM will stay much lower than 200. The result is that it had god-tier micro that changed the game completely: zergling runby’s are normally good for Zerg and bad for Protoss. With alphastar, it was the opposite, because it could micro to avoid losing any workers. Its disruptor micro was again unmatched.

Now, my last argument for why alphastar wasn’t some sort of brilliant tactician was that eventually people figured out that it’s susceptible to all the same problems a normal bot is: you can dart a warp prism in and out of its vision and it will send its army back and forth, you can confuse it by going mass raven/PF etc. and it’s completely unable to adapt. So in conclusion, no: AlphaStar doesn’t say anything one way or another about military AIs.

Re: Royal Navy says quantum navigation test a success

#39

Post by snovv_crash »

jchallis wrote: post #13

This is the most obvious practical application of my PhD topic. A Bose Einstein Condensate is an extremely sensitive detector of gravity- a nuclear submarine could use it to make an ultra-accurate map of the world based on variations in the gravitational constant g. This would remove one of the primary reasons subs need to surface , in order to GPS lock. It’s a naval chart that would not require surfacing. A French p…

Isn't this the method used by the sub in Hunt for Red October? Or did they also use a gyroscopic and look for changes in the gravitational vector, not just its magnitude?

Re: Royal Navy says quantum navigation test a success

#40

Post by verisimi »

kebman wrote: post #24

A friend of mine got PTSD from piloting huge nuclear subs in subsea ravines with a clearing of only one inch on each side of the sub. One wrong move, and the entire crew is gone. He also had to do this in conditions similar to surface storms. Looks like autonomous or automatic systems may be developed for those kinds of manoeuvres now, if it is truly that precise. Seems like a huge leap in navigational systems.

An inch! He was lucky! My friend was only given half an inch, and that was considered generous!
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