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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

#171

Post by travisgriggs »

sampo wrote: post #102
gnfargbl wrote: post #36

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).

In the TV show The Big Bang Theory, they invented a quantum vortex based inertial guidance system in 2016. Initially in https://bigbangtheory.fandom.com/wiki/The_Positive_Negative_... Then later https://www.youtube.com/watch?v=az44pMHvUYk

Came here to see if anyone else had noticed this too. :)

Re: Royal Navy says quantum navigation test a success

#172

Post by omginternets »

westurner wrote: post #131
samus wrote: post #106

Earlier quoted context omitted.

Surely the influence of some of these sources of noise can be modeled and filtered out. A University of Vienna currently conducts experiments to measure the gravitational force at very small sales, and they already have to do this with things like crowds moving about the city during rush hours.

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?

I think you may be engaged in circular reasoning, here. Noise, by definition, is what can’t be modeled. The idea would be to have some model of the signal produced by the submarine’s machinery, and use that to reduce the noise (increase SNR) to the point that this nav system becomes useful.

Re: Royal Navy says quantum navigation test a success

#173

Post by 5ersi »

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…

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

Re: Royal Navy says quantum navigation test a success

#174

Post by dekhn »

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.

I think your friend may have embellished both the accuracy and the risk (not to say that piloting a sub is completely stress free, obviously).

Re: Royal Navy says quantum navigation test a success

#175

Post by davidgay »

mertd wrote: post #168
aaron695 wrote: post #98

Earlier quoted context omitted.

> measure small variations in the earth's gravity This would be incorrect. It is just a very accurate, unproven in the field, accelerometer. https://www.youtube.com/watch?v=XwKKOPd-5cU - "Royal Navy's experimental ship carries out first trial of quantum navigation system" "The quantum accelerometer uses ultracold atoms to make highly accurate measurements. When cooled to extremely low temperatures the atoms start to…

Naive question: don't need a precise initial location to tell subsequent locations using an accelerometer? This doesn't fully obviate GPS then?

Ports don't move very often.

Re: Royal Navy says quantum navigation test a success

#176

Post by pc86 »

underdeserver wrote: post #150
1nf_ wrote: post #79

Earlier quoted context omitted.

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?

The accuracy of the reading determines the error. If today's error is so large that you have to resurface for GPS several times a day to reset it, maybe this can lower that error so you only have to resurface several times a month. Huge game changer if true.

Especially if it means you can go into enemy territory for days or even weeks before exiting to friendly or international waters to surface and reset.

Re: Royal Navy says quantum navigation test a success

#177

Post by WastingMyTime89 »

1letterunixname wrote: post #121
andyjohnson0 wrote: post #83

Earlier quoted context omitted.

I'm not a physicist but this reads like a more sensitive type of inertial navigation, which currently uses gyroscopes. https://en.wikipedia.org/wiki/Inertial_navigation_system

Vacuum mechanical gyros were used until about the 1960's when lasers (RLGs) were introduced. In the 90's, some RLGs were replaced by HRGs where space is at a premium for Q around 1e7-8. Very large RLGs are still used to detect very slow rotation and can have Q factors on the order of 1e13.

Yes, also, while I have only worked on military boats and never on subs, I can straight away tell you that anyone who would know anything remotely interesting or close to the cutting edge regarding inertial navigation system for subs wouldn't be able to talk about it.

It's one of these subjects where you will never get anything better that vague press releases designed to justify research budgets.

Re: Royal Navy says quantum navigation test a success

#178

Post by politician »

"The XV Patrick Blackett, the Navy’s new experimental vessel, provided the setting for the experiment. Sky News said the ship makes a perfect host for the futuristic experiment — it boasts a sleek design, featuring tinted windows and a glossy black hull."

Aesthetics are key for quantum navigation /s

Re: Royal Navy says quantum navigation test a success

#179

Post by roywiggins »

failbuffer wrote: post #170
Rygian wrote: post #154

Earlier quoted context omitted.

I would wonder how massive the thing on the other side of the planet has to be, in order to be detectable. The more mass necessary, the more energy you'll need to send messages. Unless the detection is extremely accurate, you would be better off spending that energy in electromagnetic radiation that bounces off the atmosphere.

For the most part yes, but for market arbitrage, the milliseconds saved by communicating thru the planet might be worth figuring out how to oscillate an extremely large weight very rapidly.

Maybe easier to use neutrinos? It has, technically, already been done at short range:

https://physicsworld.com/a/neutrino-based-communication-is-a...

Re: Royal Navy says quantum navigation test a success

#180

Post by comboy »

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…

> This would remove one of the primary reasons subs need to surface , in order to GPS lock.

Huh? Wouldn't it be enough to send some small thing connected by thin wires or wirelessly to the submarine (lasers, ultrasound, whatever) that could aquire location and communicate it? Given military budgets it could probably even be disposable.

Leaving beacons in areas of interest also seems like a good idea. With good encryption their signal could be indistinguishable from noise happening around it.

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