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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

#51

Post by kortilla »

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…

The battlefield is nothing like StarCraft though. StarCraft gives you real time control and visibility of every soldier and every enemy within the view range of any of your units. That has approximately no overlap with how command works in real militaries.

Re: Royal Navy says quantum navigation test a success

#52

Post by varjag »

julienfr112 wrote: post #44
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…

Is the gravity really constant ? I mean, big chunk of lava moving with different concentration of iron would make it change, wouldn't it?

Gravity is not magnetism, it does not care if it's iron or anything else.

Re: Royal Navy says quantum navigation test a success

#53

Post by smilespray »

andromeduck wrote: post #20
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…

Yup and it's called is called Terrain Contour Matching! https://en.wikipedia.org/wiki/TERCOM

Isn't this the old radar terrain mapping system codnamed FINGERPRINT?

It's conceptually similar, but they didn't use quantum gravity mapping in the 50s.

Re: Royal Navy says quantum navigation test a success

#54

Post by otikik »

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…

A submarine itself is quite massive, and has big moving parts (e.g. the rotor). The crew has less mass, but it would be very close, and also in constant movement. Wouldn’t this interfere with those measurements? Would they need to stop the engine and play “frozen TikTok” while the measurement device is active?

Re: Royal Navy says quantum navigation test a success

#55

Post by WinstonSmith84 »

rz2k wrote: post #14
readyplayernull wrote: post #12

Earlier quoted context omitted.

》measure gravitational effects and make deductions from that ("measure extremely accurately the influence of gravity on their system Aha! So it might be able to detect other submarines, even if they use some stealth tech.

That sounds absurd, but the $5 pressure sensor on my weather station could detect a volcanic explosion 5,000 miles away. Is there even a difference between a submarine and the surrounding water's gravitational fields when the sub has neutral buoyancy?

I'd argue that the gravity field of a sub is not uniform despite having neutral buoyancy. No idea though how significant that is vs. how sensible the measurement is

Re: Royal Navy says quantum navigation test a success

#56

Post by dumpsterdiver »

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.

[flagged]

Re: Royal Navy says quantum navigation test a success

#57

Post by beerpls »

varjag wrote: post #52
julienfr112 wrote: post #44

Earlier quoted context omitted.

Is the gravity really constant ? I mean, big chunk of lava moving with different concentration of iron would make it change, wouldn't it?

Gravity is not magnetism, it does not care if it's iron or anything else.

Um how do you figure?

Gravity cares about distance and mass, and as large parts of the planet move their density distribution shifts affecting both of those factors

Re: Royal Navy says quantum navigation test a success

#58

Post by jh00ker »

varjag wrote: post #52
julienfr112 wrote: post #44

Earlier quoted context omitted.

Is the gravity really constant ? I mean, big chunk of lava moving with different concentration of iron would make it change, wouldn't it?

Gravity is not magnetism, it does not care if it's iron or anything else.

His point was that lava density could have high-variability.

Re: Royal Navy says quantum navigation test a success

#59

Post by [deleted] »

julienfr112 wrote: post #44
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…

Is the gravity really constant ? I mean, big chunk of lava moving with different concentration of iron would make it change, wouldn't it?

[deleted]

Re: Royal Navy says quantum navigation test a success

#60

Post by jchallis »

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.

A typical sub drifts by only a few tens of meters per day - obviously this builds up . The point of the BEC gravity map is to reduce this inaccuracy an order of magnitude, thereby extending the subsurface range of the subs.
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