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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

#71

Post by kryogen1c »

otikik wrote: post #54
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?

> big moving parts (e.g. the rotor)

The shaft and screw are confined to the end of the sub. A navigation instrument like this would not be in the engineroom.

Re: Royal Navy says quantum navigation test a success

#73

Post by DaiPlusPlus »

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?

> big chunk of lava moving with different concentration of iron would make it change, wouldn't it

Why do you think the concentration of iron in magma would not be evenly distributed throughout the mantle?

Re: Royal Navy says quantum navigation test a success

#74

Post by otikik »

kryogen1c wrote: post #71
otikik wrote: post #54

Earlier quoted context omitted.

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?

> big moving parts (e.g. the rotor) The shaft and screw are confined to the end of the sub. A navigation instrument like this would not be in the engineroom.

It is still way closer to the instrument than the deep end of the sea, most of the time. Square of distance is a very potent thing.

I am reminded of this:

https://www.theguardian.com/science/2015/may/05/microwave-ov...

Re: Royal Navy says quantum navigation test a success

#75

Post by DaiPlusPlus »

snovv_crash wrote: post #39
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?

I haven't read the book, but in the film the problem was the Red October was using the caterpillar-drive https://en.wikipedia.org/wiki/Magnetohydrodynamic_drive (and not a propeller/impeller) but a chance detection by Dallas' sonar along with the ingenuity of Dallas' sonar operator, who figured out how to detect and track Sean Connery's boat. Nothing to do with gravity or gyroscopes at all.

Re: Royal Navy says quantum navigation test a success

#76

Post by sph »

dumpsterdiver wrote: post #56
HyperSane wrote: post #26

Earlier quoted context omitted.

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]

> any stable solar system capable of sustaining life will emit a steady heartbeat, just like a living being

What do you mean? What would be the source of the regular wave-like signal, and why only systems with life have one?

Do you mean that actual hearts beating create gravitational waves?

Re: Royal Navy says quantum navigation test a success

#77

Post by marginalia_nu »

verisimi wrote: post #40
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!

Yeah, of course we had to row the damn thing too. Uphill and sub-freezing temperatures, both ways.

Re: Royal Navy says quantum navigation test a success

#78

Post by defrost »

marginalia_nu wrote: post #77
verisimi wrote: post #40

Earlier quoted context omitted.

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

Yeah, of course we had to row the damn thing too. Uphill and sub-freezing temperatures, both ways.

True story . . .

https://www.amusingplanet.com/2016/09/this-wooden-barrel-was...

Re: Royal Navy says quantum navigation test a success

#79

Post by 1nf_ »

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…

The majority of INS platform drift is from a thing called "tilt error" - where the IRS initially misjudges the exact direction of the gravitational vector during alignment. All this will do is improve the accuracy of the accelerometers but will still have the drift caused in the INS itself. How will this make such a large improvement over what we have already?

Re: Royal Navy says quantum navigation test a success

#80

Post by mnw21cam »

K0balt wrote: post #66
sakras wrote: post #38

Earlier quoted context omitted.

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…

The word is pwned, not pawned, by the way. I suspect your autocorrect, as well as op’s has had it’s way with your prose. I often wonder how much autocorrect will shape the evolution of language.

s/it's/its/
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