Quantum Compass to eventually replace GPS

[Ron]

Interesting article about newer technology in the pipeline. GPS has become so pervasive but of course we are completely dependent on the governments of the world to maintain the arrays. This technology if it could be made hand held would be a game changer.

Scientists at Porton Down and the National Physical Laboratory believe they are three to five years away from developing a “quantum compass” that would be able to locate itself based on the subatomic effects of the earth’s magnetic field.

The technology, which would have no need for satellites or fixed points of reference such as radio masts, is of military interest around the world, because of the limitations of space-based navigation systems.

http://www.ft.com/cms/s/0/4cac5a24-db68-11e3-94ad-00144feabdc0.html#axzz31nq8JMQI

[RoadKingLarry]

ft.com want a registration, free or not they are out of luck.

From the limitid info in the OP though it sounds like a good idea. Particularly since we are systematicaly dismantling our ability to operate and maintain space based equipment.

[Northwoods]

Cool thing about that tech, if it ever works, is dark timber, even deep underground bunkers wouldn't prevent a location lock.

[230RN]

Search term "quantum compass"

Sample hit:
http://members.jacksonville.com/opinion/blog/400564/john-leacock/2014-05-15/science-journal-quantum-compass-promises-be-better-gps

How does a quantum compass work?

According to the Daily Mail:

Ultra cold atoms are cooled with lasers to temperatures a billion times colder than outer space.
At their lowest energies the atoms become the coldest known bodies in the universe.
These slow moving, low energy atoms are extremely sensitive to changes in the earth’s magnetic and gravitational field.
If trapped on a small device, their tiny fluctuations can then be tracked from great distances and their locations pinpointed with a huge degree of accuracy.

READ THE STORY in The Daily Mail

First question is what they mean about cooling things by lasers a "billion times colder than outer space."  (And shouldn't that be "infra" cold instead of "ultra" cold? :D )

Second question is regarding stray magnetic fields and magnetic anomolies in the earth's crust.

Third is regarding the shifting strength and locale of the Earth's poles.

While it would seem that just about every point on or above the earth has its own magnetic characteristics (strength, inclination, declination)  these characteristics change over time--- position by 40 miles per year, strength by about 10% recently.

So I wonder about how this thing is supposed to work unless they update the base data in the one in your backpack frequently.... by satellite?

I'm willing to learn.

Terry, 230RN

[T.O.M.]

And what about the polar reversal???  I saw an episode of Doomsday Preppers where a guy said that the poles are going to reverse anytime now, and the entire planet will be thrown into chaos.  How will I know which way to walk home if the poles reverse and my new super magnet won't tell me which way I need to walk???   

[KD5NRH]

"billion times colder than outer space."

How do they get them so far below 0K?   Is there really that much hard science behind it, or are they just so damn cold they always pull towards Hawaii?

[brimic]

How do they get them so far below 0K?   Is there really that much hard science behind it, or are they just so damn cold they always pull towards Hawaii?

I wondered about that as well.
0K is sort of like the speed of light, its possible to go colder, but the best we can do with current levels of technology is approach 0K, not actually reach it.

[Marnoot]

I believe the danger with a magnetic polar reversal happening is the time during the reversal when Earth's magnetosphere isn't coherent enough to protect us from the nasty high-energy particle radiation coming at us from the sun.

I understand a very basic level how they "cool" the atoms down (use a laser to (very nearly) stop the atom's motion/vibration), though that's not really a pocket-size device. I don't understand how they could possibly "trap" said atoms in a small device. Wouldn't the atoms just warm back up?

[AJ Dual]

How do they get them so far below 0K?   Is there really that much hard science behind it, or are they just so damn cold they always pull towards Hawaii?

http://en.wikipedia.org/wiki/Laser_cooling

When they say "a billion times colder" they're talking about logarithmic or some other exponential scales that measure the energy of electrons and atomic properties as you approach absolute zero or maybe a Bose-Einstein Condensate. So cold, or appropriately, a state of matter where there is so little heat, the wave functions of whole atoms or particles can superimpose.

Kind of like how the sun's corona has a temperature of 10 Million degrees, but if you were exposed to that, and shielded from the direct light of the photosphere, you'd still die of vacuum exposure and freeze-dry from rapid evaporating cooling as your body fluids boiled. The plasma might have a "temperature" of millions of degrees, because of their energy state, but on the macro-scale, it's almost the same thing as hard vacuum, and your flesh will react accordingly.

Sort of a nebulous concept, but there's "heat" as humans know it, "heat" as chemistry knows it, and "heat" as physics knows it.

[230RN]

How do they get them so far below 0K?   Is there really that much hard science behind it, or are they just so damn cold they always pull towards Hawaii?

I "got" that, not in terms of going below 0K, but a billion times colder than whatever you measure.

If you're measuring a temperature of 0.001K, then a billion times colder than that would be,

0.000000000001K.

Shucks, "all" you gotta do is move the decimal point 9 places to the left. :D  (Or twelve if you're British. :D :D )

As far as cooling with a laser goes, I've gotta read A.J. Dual's citation. That may take a while.

But I still wonder how the system will cope with Earth's changing magnetic field without daily or weekly updates.  And with disruptions of the system by proximity to an electric motor.  Or the neodymium(sp?)  magnets on your refrigerator.

Or your subwoofer speakers. :)

" 'Tis a puzzlement."

Terry

PS. I'm aware that "a billion times colder" really means "one billionth of the heat," but I'm using their lingo.