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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

#201

Post by L_226 »

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…

Yeah, and if you put one in some kind of "spy balloon" you could also use it to map secret underground structures that may or may not exist in certain parts of the US ;)

Re: Royal Navy says quantum navigation test a success

#202

Post by Karliss »

rtkwe wrote: post #189
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…

It'd be interesting to see if they're sensitive enough to do the opposite detect the gravity anomaly that is the sub. There's a couple near future submarine warfare books where that's one of the devices used to attempt to find subs.

Gravity force is proportional to mass and the average density of submarine is close to water density so (possibly slightly less as positive bouyancy is preferable for safety reasons) so gravity force produced by submarine should be very close to the equivalent volume of water. So instead of detecting big chunk of metal (which is still relatively small for the scale of gravity), sensor would have to be sensitive enough to detect mass distribution within submarine or the minor density difference due to slight positive bouyancy.

Re: Royal Navy says quantum navigation test a success

#203

Post by RationPhantoms »

rtkwe wrote: post #190
5ersi wrote: post #173

Earlier quoted context omitted.

Doesn't magnetic pole shift due to fluid dynamics in Earth core? Wouldn't that also affect gravity field?

Yes it does but we also have satellites mapping those shifts so it could be accounted for. The big question is are those fine grained enough to resolve the errors in modern INSs.

Wouldn't that then require communication with those satellites to receive the shift/drift info? Doesn't that eradicate the point of a navigational system without reliance on GPS/satellites?

Or is the drift is so minor that this quantum navigation system can operate for up to 6 months without sufficient core drift alignment calculation?

Re: Royal Navy says quantum navigation test a success

#204

Post by sakras »

kebman wrote: post #191
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…

[flagged]

> Also AlphaStar can teach absolutely nothing to the army tacticians.

This is the only sentence of your summary that accurately portrays my comment.

I do think they are investing in tactical AIs, you even see it with those new loyal wingman UAVs. But the notion that AlphaStar proves that we already have tactical AIs that outperform humans is absurd.

Re: Royal Navy says quantum navigation test a success

#206

Post by sakras »

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.

That’s hilarious, I did actually write “pawned” intentionally, but while writing it I thought, “Haven’t heard this one before, but I guess it makes sense, it treated them like pawns in chess”

Re: Royal Navy says quantum navigation test a success

#207

Post by sampo »

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…

> It’s a naval chart that would not require surfacing.

Other sources say this is about inertial navigation, not based on charts.

"Accelerometers measure how an object’s velocity changes over time. With this, and the starting point of the object, the new position can be calculated."

https://www.imperial.ac.uk/news/188973/quantum-compass-could...

Re: Royal Navy says quantum navigation test a success

#208

Post by westurner »

samus wrote: post #137
westurner wrote: post #131

Earlier quoted context omitted.

Sources of Noise ?! Doesn't that mean that the gravitational field is an information storage and transmission medium; a signal channel? Is it lossy? Is there a routable signal path to block harassing calls? Is it slower or cheaper than nonlocal entanglement; like quantum radar? What is the minimum energy necessary to cause a propagating thresholdable-as-binary pertubation of a gravitational field?

Not a formal definition, but noise is simply the undesirable parts of the output of any information processing device, be it a sensor, an amplifier, or a transmission medium. But on Earth it's simply not practical as such. Gravitational waves observatories are used to detect events such as neutron star or black hole mergers that are otherwise unobservable, but they require an insane level of precision to be detected.

Are there yet any instruments better than LIGO at a lagrangian point outside Earth's atmosphere and the Van Allen radiation belt?

Re: Royal Navy says quantum navigation test a success

#209

Post by jackdh »

clintfred wrote: post #194
jackdh wrote: post #68

Earlier quoted context omitted.

It's off topic however on the people page[0] of the above link, I enjoyed going through to try and spot the photoshopped in ones! [0] https://www.imperial.ac.uk/centre-for-cold-matter/people/

That was fun. That whole left side has a lot of suspicious lighting, doesn't it?!

Indeed! There is also a mystery leg between the legs of the second chap in from the right.
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