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Physicists Devise Magnetic Shield

samzenpus posted more than 2 years ago | from the leave-your-emp-gun-at-home dept.

Science 90

sciencehabit writes "The sneaky science of 'cloaking' just keeps getting richer. Physicists and engineers had already demonstrated rudimentary invisibility cloaks that can hide objects from light, sound, and water waves. Now, they've devised an 'antimagnet' cloak that can shield an object from a constant magnetic field without disturbing that field. If realized, such a cloak could have medical applications, researchers say."

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Metal Detectors? (2)

cheater512 (783349) | more than 2 years ago | (#37486094)

Would this not cause a security nightmare?

Re:Metal Detectors? (1)

O('_')O_Bush (1162487) | more than 2 years ago | (#37486108)

Well, it says constant magnetic field. That's pretty hard to generate, since lots of things cause magnetic fields to fluctuate (including body movement of a metal object).

Re:Metal Detectors? (4, Informative)

icebike (68054) | more than 2 years ago | (#37486178)

Well, it says constant magnetic field. That's pretty hard to generate, since lots of things cause magnetic fields to fluctuate (including body movement of a metal object).

TLDR version of TFA:

The hypothetical device would work as a magnetic cloak by creating a space that is protected from an external magnetic field while at the same time causing no telltale distortion of the field. Alternatively, it could also be used to conceal a magnetic object and prevent its magnetic field from extending out into space—

So, yeah, if made portable enough it would be a security problem. But don't hold your breath.

Re:Metal Detectors? (2)

Delarth799 (1839672) | more than 2 years ago | (#37486734)

So we should expect to walk through the hyper x-ray scanner 9000 naked in the next few months just as a precaution to such evil devices then

Re:Metal Detectors? (1)

robot256 (1635039) | more than 2 years ago | (#37486946)

This is shielding against *magnetic* detection, i.e. conventional metal detectors, not your favorite neighborhood X-ray body scanners.

Invisible Submarines (1)

arisvega (1414195) | more than 2 years ago | (#37490204)

Forget about metal detectors. This can make submarines invisible. [wikipedia.org]

Re:Invisible Submarines (0)

Anonymous Coward | more than 2 years ago | (#37493078)

Forget about metal detectors. This can make submarines invisible.

You're proposing to cover an entire submarine in liquid nitrogen? That's insane, especially when magnetic anomaly detectors are easy to avoid.

Even so, the submarine must be very near the aircraft's position and close to the sea surface for detection of the change or anomaly.

Re:Metal Detectors? (1)

rgbatduke (1231380) | more than 2 years ago | (#37491646)

Not necessarily naked. And I get patent-dibs on the horizontally polarized transparent plastic coveralls with "Fly Clear" stencilled on the front. And on the vertically polarized sunglasses everybody will have to wear to preserve modesty, unless they tip their head sideways to get a peek at that absolutely gorgeous stacked blonde. Although, given the fat tattooed lady in between with a bit of paper stuck between the cheeks, most of us will probably opt to keep our heads straight up...:-)

rgb

Re:Metal Detectors? (1)

MacGyver2210 (1053110) | more than 2 years ago | (#37487678)

The Microwave shielding material is like a foil. I think it is feasible this is already in use by those secretive black-hat folks.

Re:Metal Detectors? (2)

Solandri (704621) | more than 2 years ago | (#37488498)

Sounds more like something to help hide submarines from MADs [wikipedia.org] .

Was the TSA thinking ahead? (1)

Anonymous Coward | more than 2 years ago | (#37486158)

Perhaps this is the justification for restricting liquids on airplanes: presumably a liquid is required to cool the conductor to make it a superconductor.

Re:Was the TSA thinking ahead? (1)

izomiac (815208) | more than 2 years ago | (#37486638)

Encase the superconductive shielding in aerogel or a similarly effective insulator, and use high-temperature superconductors. You should be able to get enough time out of that arrangement to make it past security, plus it's now thermally shielded (not cloaked).

But I doubt that's technically a problem. You see, the TSA categorizes substances by their phase of matter at room temperature. That's why they won't allow normal ice but dry ice is OK. Liquid nitrogen, helium, or hydrogen should be OK then, as they're all gases at room temperature. Unless the TSA is logically inconsistent... (Although I've got a nagging feeling that logic alone won't get you very far with the executive branch of government... Or the legislative... Fingers-crossed for the judicial...)

Re:Was the TSA thinking ahead? (2)

hot soldering iron (800102) | more than 2 years ago | (#37486982)

Wow. An electromagnetic shield to get "something" by TSA scanners? I'm pretty sure I could just hire a baggage handler to put "something" on board, without ever seeing a scanner. If money doesn't work, threatening his loved ones would.

Yeah, that was evil, and I went there. Other people would, too.

Re:Was the TSA thinking ahead? (1)

izomiac (815208) | more than 2 years ago | (#37487638)

It's a security theater. But obviously it's no fun to devise clever methods of evading security when your opponent in the cat-and-mouse-game is worse than Garfield.

Re:Was the TSA thinking ahead? (1)

black soap (2201626) | more than 2 years ago | (#37490174)

Wait, is the TSA the cat, or the mouse? Because we haven't seen all that much cleverness on either side of the game in a while. I mean seriously, shoe-bomb that doesn't work, followed by underwear bomb that doesn't work? the only thing remotely clever was the pepto-bismol-as-xray-shield, which would have worked except for the TSA gets slightly curious when things show opaque on an xray of your carry-on.

Referring to TSA-vs-the enemy as a "cat-and-mouse-game" is insulting to both cats, and mice.

Re:Was the TSA thinking ahead? (1)

black soap (2201626) | more than 2 years ago | (#37490090)

I think it is pretty obvious the TSA wasn't thinking.

Just to humor the idea, though, I'm pretty sure compressed gas and cryogenic liquids were already not allowed. Although someone did try to use pepto-bismol to hide stuff from the xray machine.

Re:Metal Detectors? (2)

ceoyoyo (59147) | more than 2 years ago | (#37488022)

Sure! The metal detector would be useless. You might want to search the guy walking through with a big bundle venting white vapour though.

You are absolutely correct! (0)

Anonymous Coward | more than 2 years ago | (#37488274)

Yes, loss prevention officers at malls need to be on the lookout for shifty-looking people who are toting dewars of liquid nitrogen. Of course, we presume that type II superconductors will be adequate to handle those pesky anti-shoplifting tags. If not, then those bastards will no doubt resort to using the readily-available liquid helium.

"Don't mind this, it's my superconducting blanket with liquid nitrogen feed. I have a doctor's note. See?"

...and then, sadly, the cryoshoplifters get busted by the fact that the shoplifting scanners use phased magnetic fields from electromagnetic arrays rather than a bunch of permanent magnets mounted in the vertical mounts.

But you know, if the scanners suck and you can carry around a superconductor with you to the mall, you could make bank! Where do I sign up?

Re:Metal Detectors? (1)

jamesh (87723) | more than 2 years ago | (#37488340)

Would this not cause a security nightmare?

Agreed. Metal detectors are useless. Cavity searches for all!

Re:Metal Detectors? (2)

JustOK (667959) | more than 2 years ago | (#37489490)

my dentist says I have no cavities.

Re:Metal Detectors? (0)

Anonymous Coward | more than 2 years ago | (#37493442)

And my dentist filled all my cavities.

Oh, wait, that doesn't sound right.

Professor X needs one of these (0)

Anonymous Coward | more than 2 years ago | (#37486130)

n/t

Kind of disappointing (2)

theguyfromsaturn (802938) | more than 2 years ago | (#37486170)

From reading the headline I was almost expecting a shield a la Star Trek. All we would have left would be to find a way to make the Alcubierre warp drive something more than a theoretical possibility and I'd be donning Vulcan ears. Oh, well, I guess the waiting is not almost over yet.

Re:Kind of disappointing (3, Insightful)

Commontwist (2452418) | more than 2 years ago | (#37486358)

Hey, if it, or some variation of it, could help shield a spacecraft from the Van Allen belts I'd call it a win.

Re:Kind of disappointing (2)

gumbi west (610122) | more than 2 years ago | (#37492948)

The Van Allen belt is not problematic because of the magnet, it is the particles caught in the magnetic field that are the problem. They are flying around in circles, stuck forever (well, until they interact or decay). Dampening the field in one area would just make them fly straight for a bit, but they would be just as harmful as they were when they were flying in curly cues.

Re:Kind of disappointing (1)

BJ_Covert_Action (1499847) | more than 2 years ago | (#37493182)

For that matter, if it could be scaled down small enough, it could really help isolate spacecraft components from EMI interference by other spacecraft components.

Re:Kind of disappointing (1)

Can't we get along (1939026) | more than 2 years ago | (#37486380)

Agreed. The headline should have read "Physicists Devise Magnetic Cloak". It would still have been cool.

Re:Kind of disappointing (-1)

Anonymous Coward | more than 2 years ago | (#37486388)

Shucks, if only "science" *fiction* had even the slightest, remotest connection to reality, eh? Look, up in the sky! It's the same 747 since 1969! Shame there's no physics to allow the demented lunatic fantasies from the pages of sci-fi.

Re:Kind of disappointing (1)

JordanL (886154) | more than 2 years ago | (#37486448)

How is providing artistic interpretation of imagined realities demented or lunatic?

Re:Kind of disappointing (0)

Anonymous Coward | more than 2 years ago | (#37488768)

It is when you think they aren't "artistic interpretation", but engineering blueprints and it's just the evil government preventing us from colonizing the galaxy, and not, say, reality.

Oh, and "imagined realities" would be psychotic, to say the least. If it's imagined, that's all it is, it's not real.

Re:Kind of disappointing (1)

JordanL (886154) | more than 2 years ago | (#37489226)

I truly feel sorry for you. You are so stuck in "left brain" thinking that you don't even seem to understand what I'm saying, although you understand each of the words.

Re:Kind of disappointing (1)

Wyatt Earp (1029) | more than 2 years ago | (#37487184)

No, the 747 from 1969 is the 747-100, almost all are retired.

Most 747s you see now are 747-200s and -400s, from the 1980s through production today.

Re:Kind of disappointing (0)

Anonymous Coward | more than 2 years ago | (#37488670)

Same altitude, same materials, same Brayton cycle turbines, same fuel. The logical extension to that is not "Space Elevator", it's "this is *it*".

Re:Kind of disappointing (1)

slackbheep (1420367) | more than 2 years ago | (#37488986)

How long were we making the same old stone axes before our tool development really took off? Up till something like 250,000 years ago? Regardless commercial aviation is an odd thing to choose to make this point given that technology has moved forward, it's simply not been cost effective to adopt. Consider the Concorde, not to mention the slow growth of space tourism. This is not to argue for the feasibility or inevitability of a space elevator, just pointing out that there are plenty of older technologies around that aren't really going anywhere generally because it accomplishes it's task efficiently enough.

Re:Kind of disappointing (1)

black soap (2201626) | more than 2 years ago | (#37490288)

How many people did we have in stone-axe R&D at the time, and how was their communication? Right now, we have a lot more people sharing a lot more ideas than at any point in history. We also have better ways to communicate ideas, including preserving them for later, as developed pretty recently.

Re:Kind of disappointing (1)

TheLink (130905) | more than 2 years ago | (#37490966)

There are now a lot more patents preventing lots of people from doing stuff without cross-licensing agreements or court cases.

A lot of smart folk who want to make money have gone into investment banking instead.

Also many smart people who want to make cool stuff are not doing it in aerospace. There are many other fields.

I don't get it. (0)

Anonymous Coward | more than 2 years ago | (#37488064)

what does this have to do with sharks and lasers?

Magnets! How do they work? (0)

Anonymous Coward | more than 2 years ago | (#37486196)

Not as well as we thought, apparently.

Score one for ICP (sigh).

MRI can be much better with this (1)

Palpatine_li (1547707) | more than 2 years ago | (#37486224)

Now the problem with raising the magnetic field strength to get higher resolution is the the distortion of the field. Most of this distortion can be avoided just by shielding everything except what you are going to image in this magnetic shield.

Re:MRI can be much better with this (2)

Cosgrach (1737088) | more than 2 years ago | (#37486604)

MRI suites are already shielded.

And no, you can not shield the specific volume (inside the magnet) to be imaged.

Re:MRI can be much better with this (1)

ceoyoyo (59147) | more than 2 years ago | (#37488036)

The problem is homogeneity of the field. And no, this won't help. To get a homogenous, strong magnetic field over a reasonably sized volume (head size, for example) requires a big magnet with a lot of coils. Thus, expensive. "Distortion" has nothing to do with it.

Re:MRI can be much better with this (1)

Rhywden (1940872) | more than 2 years ago | (#37488338)

I'd rather say that SQUIDs should profit from this technique. http://en.wikipedia.org/wiki/SQUID [wikipedia.org]

Re:MRI can be much better with this (1)

ceoyoyo (59147) | more than 2 years ago | (#37489764)

Why is that? Why would you want to put your magnetometer into a device that cloaks it from external detection?

If you mean screening out external fields to make a quieter environment, you can do that just fine using existing shielding techniques.

Re:MRI can be much better with this (1)

Talderas (1212466) | more than 2 years ago | (#37489476)

I was thinking it could be used in conjunction with MRIs, but in a different way...

Could this shielding be used on devices that are too sensitive to allow MRIs (like pacemakers) so that the recipient of the device would be allowed to obtain MRIs?

Re:MRI can be much better with this (2)

ceoyoyo (59147) | more than 2 years ago | (#37489918)

Personally, I'd prefer not to have a pacemaker with a large, cryogenically cooled shield around it. Walking around with a liquid nitrogen can and hoses going into my chest would seriously cramp my lifestyle.

I'm not even sure it would work properly - most of the danger to metallic implants, particularly sensitive electronic ones, in an MRI is from RF signals, not the magnetic field.

Think of the Quackery (5, Insightful)

ZombieBraintrust (1685608) | more than 2 years ago | (#37486228)

Forget the actual medical applications. The applications for pseudo medicine are just as good. There are already a ton of people sleeping on magnetic mats. They would eat this up. Maybe even literally.

Re:Think of the Quackery (1)

icebike (68054) | more than 2 years ago | (#37486642)

Forget the actual medical applications. The applications for pseudo medicine are just as good. There are already a ton of people sleeping on magnetic mats. They would eat this up. Maybe even literally.

My kingdom for a mod point!!!

Re:Think of the Quackery (1)

ThreeGigs (239452) | more than 2 years ago | (#37487256)

Forget both medical and pseudo medical. If you can shield something from a magnetic field, you can create a perpetual motion machine. Two magnets pull towards each other, generating energy, one gets shielded, move them away from each other, repeat.

The possibility of a magnetic shield seems to break some thermodynamic laws, unless I am misunderstanding something.

Re:Think of the Quackery (1)

bronney (638318) | more than 2 years ago | (#37487372)

what is "move them away from each other"?

Re:Think of the Quackery (0)

Anonymous Coward | more than 2 years ago | (#37487400)

Placing the shield around the magnet would require at least as much energy as you get from moving the unshielded magnet into the field.

Re:Think of the Quackery (2)

Sabriel (134364) | more than 2 years ago | (#37487706)

The possibility of a magnetic shield seems to break some thermodynamic laws, unless I am misunderstanding something.

The laws of conservation indicate the energy input to separate the two fields will meet or exceed the energy output from trying to pull perpetual motion shenanigans.

And after RTFA, it's a materials-based cloak; you can't simply toggle it on/off, and moving the materials generates energy transfers which obey the conservation laws. :)

When you consider the way the cosmos is set up, building an actual working perpetual motion machine might well involve safety warnings along the lines of "Please do not operate within inhabited continuum" or "Warning: no (n<5)-dimensionally serviceable parts inside". :p

Re:Think of the Quackery (0)

Anonymous Coward | more than 2 years ago | (#37488230)

Personally I've always thought of them more as guidelines

Re:Think of the Quackery (0)

angel'o'sphere (80593) | more than 2 years ago | (#37489372)

As you obviously don't know much about thermodynamics, you likely can not judge if one is broken, or?

After all: magnetic fields have nothing to do with thermodynamics (the word thermo comes from temperature and means HEAT). Thermodynamics applies to heat related physics ...

Re:Think of the Quackery (1)

angel'o'sphere (80593) | more than 2 years ago | (#37502572)

And why is one again down modding me? Especially why is it rated "troll"?

Re:Think of the Quackery (0)

Anonymous Coward | more than 2 years ago | (#37492388)

Exactly! Magnetic perpetuum mobile was the first thing that I thought of when hearing about the magnetic shield. I was toying with that idea since childhood, but the only possibility to make it was using superconductors and magnetic monopoles, which requires way too much energy to maintain.

Re:Think of the Quackery (1)

ceoyoyo (59147) | more than 2 years ago | (#37488056)

There are no actual medical applications. Somehow I think a patient will object to being opened up, their implant surrounded by a large, layered device containing liquid nitrogen or helium, then scanned. It would be easier just to remove the implant, scan, then put it back.

Re:Think of the Quackery (1)

dougmc (70836) | more than 2 years ago | (#37488282)

Forget the actual medical applications. The applications for pseudo medicine are just as good. There are already a ton of people sleeping on magnetic mats. They would eat this up. Maybe even literally.

I'm not so sure ...

I mean, I certainly do believe that some people feel that magnetic fields (even static ones like the one created by the Earth) are making them sick -- but the technology to stop this in a room has been around for decades -- it's called a thick magnetic metal (iron, steel) box. If you've got a large budget and it needs to be as perfect as possible -- make it out of mu-metal [wikipedia.org] . Usually this is used for scientific and other work where reducing the magnetic field as much as possible really matters -- but if somebody really is afraid of the effects that magnetic fields have on their body, they have been able to do something about that for a long time now.

It sounds like the key to this new discovery is not disturbing the magnetic field -- but that's not important if your goal is simply to have a space devoid of a magnetic field.

Re:Think of the Quackery (1)

CODiNE (27417) | more than 2 years ago | (#37489848)

Oh the other hand, maybe it'll let us make the time machine from Primer.

hehehe

Re:Think of the Quackery (0)

Anonymous Coward | more than 2 years ago | (#37492656)

If such shielding can be made highly directional, then I've got some ideas for magnet motors. Who needs to play with the medical stuff?

Gravity Shield? (0)

Anonymous Coward | more than 2 years ago | (#37486274)

Can they make a gravity shielding device?

Ethereal (0)

Anonymous Coward | more than 2 years ago | (#37486406)

There have been many interesting studies on the topic of electro-gravitism, Mr. Smith. The real question is -are humans ready to utilize it?

Perpetual motion machine! (0)

Anonymous Coward | more than 2 years ago | (#37486338)

Imagine a clock face, even hours magnetically shielded, odd hours not. Now imagine a set of pistons arranged in a circle below and a set of permanent magnets above. Spin the clock face so the pistons rise towards the magnets, then fall with gravity as you shield them.

World's problems: solved.

Re:Perpetual motion machine! (0)

Anonymous Coward | more than 2 years ago | (#37487206)

Steorn Effect [youtube.com]

Go nuts.

Break energy conservation? (-1)

Anonymous Coward | more than 2 years ago | (#37486378)

This would break the laws of Physics because you could use it to shield one side of a magnet and then make an infinite motor that could then power a generator that would generate electricity forever for free.

Re:Break energy conservation? (1)

hedwards (940851) | more than 2 years ago | (#37486562)

It would have to be 100% efficient to even attempt that. Otherwise you'd lose energy in the conversion process and as a result end up with less energy than you had, rather than more.

Re:Break energy conservation? (1)

headhot (137860) | more than 2 years ago | (#37487236)

Also, you have to take into account the energy to make the shield.

Re:Break energy conservation? (1)

fnj (64210) | more than 2 years ago | (#37487758)

Nonsense. If the explanation as summarized is accurate you could use a permanent magnet. Let it attract an iron object on a string wound around a generator. As the object is attracted, the generator produces electricity. Normally, you have to EXPEND just as much energy to pry the object away from the magnet again. But if instead you introduce this "magic shield" between the magnet and the object just before they touch, you can pull the object away again for almost no energy expenditure. Rinse, lather, and repeat over and over again and you produce an infinite number of surges of electricity for next to no energy input. Even a generator of 5% efficiency would be plenty to provide perpetual motion plus energy coming out to run you TV (after being suitably converted, filtered and leveled).

Of course a real device would be much more sophisticated than the above mind exercise, but the above is enough to show that it breaks the law of conservation of energy.

So no, I do not think the summary as given is accurate, because I believe in the law of conservation of energy.

Re:Break energy conservation? (1)

angel'o'sphere (80593) | more than 2 years ago | (#37489394)

You forget one thing in your example:
the object you pull has to be placed back at its starting position. That costs exact the same amount of energy you have earnt before. So even with a magnetic shield device (I strongly suggest you read the article instead fo the /. summary) a machine like the one you describe is no perpetuum mobile. The laws of energy conversion are still hold up.

Re:Break energy conservation? (1)

jkflying (2190798) | more than 2 years ago | (#37490430)

According to the laws of thermodynamics, the power to create the shield would be the same or more than the power you could gain there. Makes sense, really.

Re:Break energy conservation? (1)

Mindflux0 (2447336) | more than 2 years ago | (#37487476)

magnets don't have sides.

What do you mean by "shield one side"?

If you physically cut the magnet in half, you just have two magnets. If you left the magnet intact you wouldn't be able to shield it from itself. Unless maybe you had an infinite length shielding device spanning the whole universe...

hmmm...

trolled weren't I now?

Better headline (3, Informative)

pz (113803) | more than 2 years ago | (#37486408)

A better headline would be, Physicists Come up with Idea to Build Perfect Magnetic Shield. As the article states, the device itself is hypothetical no proof of concept has been built.

Re:Better headline (1)

Ihmhi (1206036) | more than 2 years ago | (#37486624)

A better headline would be, Physicists Come up with Idea to Build Perfect Magnetic Shield. As the article states, the device itself is hypothetical no proof of concept has been built.

I'd say "Come up with idea" and "Devise" are pretty much the same thing.

Re:Better headline (0)

Anonymous Coward | more than 2 years ago | (#37487976)

Memristors were hypothetical until a few years ago.

Wipers had this back in the 80's... (1)

Mhrmnhrm (263196) | more than 2 years ago | (#37486564)

...or am I the only one around who remembers that totally cheesy, yet elementary schoolkid riveting, post-apocalyptic edutainment show "Tomes and Talismans"

This is news how? (3, Informative)

Cosgrach (1737088) | more than 2 years ago | (#37486574)

Okaaaaaay. I hate to break it to you guys, but passive and active magnetic shielding has been around for a long time now. This is simply a new spin on old tech, adapting it and slightly enhancing it.

Shielding an object from external fields is not difficult provided you have money to spend. Hospitals do it all the time for their MRI suites. The shielding may be either passive (LOTS of steel plates in the floor, walls and ceiling), or actively by installing 3-axis helmholtz coils in the walls, floor and ceiling. The coils are then driven by a set of very large and fast amplifiers. The amplifiers are driven by correction signal from a computer that has at least one 3-axis magnetometer. Obviously, the active solution is better as it can correct for things like elevators, automobiles and other things that influence the local magnetic field. The passive shielding is only good is the external field does not change.

I remember one such shielding job in San Francisco that gave trouble because of the volume of *WATER* flow in the city water main running under the MRI suite. Yes, even water can affect magnetic fields. Passive shielding would not work, so the site had to switch to the more expensive active shielding.

I also have had trouble calibrating magnetic instrumentation because of cars in the car park moving around. I'd have to wait for a window where there was no activity outside the building. I'm talking about smallish cars more than 50' away, and large trucks could change the fields from more than 100' away...

Re:This is news how? (4, Informative)

robot256 (1635039) | more than 2 years ago | (#37486974)

Everything you said is true, but all those methods of shielding an enclosed space can be detected from outside the space by the resulting warp in the fields around it. The researchers in this article propose a method of layering materials so that the warping of the field is contained within the shield itself, rendering its presence undetectable. This is a significant advance over conventional shielding, but it has yet to be proven feasible.

Re:This is news how? (1)

50000BTU_barbecue (588132) | more than 2 years ago | (#37487228)

Imagine having to anneal a Mumetal can the size of a MRI room?

Re:This is news how? (1)

mikael (484) | more than 2 years ago | (#37491568)

Certain water meters operated by actually measuring the distortion of the base level magnetic field due to the presence of ions in the water (metals from minerals, leeched elements from the pipes along with hydrogen and oxygen).
The water meter was simply a ring of copper put around the pipe. Any changes in the flow of water created a fluctuation in the magnetic field, which in turn creates a current in the coil.

Normally, these were intended for small pipes, but I guess it scales up for large pipes.

Nimrod airplanes were used to detect submarines in this way. Even though they were underwater and had been de-Gaussed, they would still distort the magnetic field.

I guess if magnetic shielding can be made to work in real-world environments, we'll move over to gravitometric detection methods like they use in Iraq/Afghanistan to detect underground tunnels.

Immediate Military Applications (1)

Anonymous Coward | more than 2 years ago | (#37486636)

Two I can think of:

  • Minesweeper ships - they don't want to trigger a mine's magnetic sensors, and are usually constructed entirely of wood and fiberglass.
  • Submarines - Don't want to be detected by mines or anti-submarine aircraft

Carriers and other high-value ships are probably too big to use this. I'm not sure if their escorts would want this as much.

Any more?

Re:Immediate Military Applications (1)

Wyatt Earp (1029) | more than 2 years ago | (#37487202)

Warships are usually degaussed before a deployment and it can be and has been used in ships as large as a battleship. Carriers might be carrying electromagnetic coils as they did in WW2

http://en.wikipedia.org/wiki/Deperming [wikipedia.org]
http://en.wikipedia.org/wiki/Degaussing [wikipedia.org]

Re:Immediate Military Applications (4, Interesting)

izomiac (815208) | more than 2 years ago | (#37487800)

Landmines. Right now, they use a bare minimum of metal to evade metal detectors, so everything is mechanical. This would allow a processor and such to be in the mine so you could have it not detonate on friendlies, and deactivate itself/start beeping after a couple years. Heck, you could even have the mines networked so the whole field detonates simultaneously when it detects large number of troops are half-way across. I'm not sure if it's in the best interest of humanity to revisit this technology, but at least some of their tactical and humanitarian problems can be addressed.

WATER waves? (1)

ludomancer (921940) | more than 2 years ago | (#37486744)

Can someone link me that story? Must have missed it. How do you shield something from water waves?

Re:WATER waves? (1)

ThorGod (456163) | more than 2 years ago | (#37487304)

Setup a standing wave of equal intensity but with (exact) opposite phase. (I think.)

Re:WATER waves? (0)

Anonymous Coward | more than 2 years ago | (#37489990)

More importantly, how is a water wave any different fundamentally from a sound wave (other than the obvious fact that one connotes millihertz while the other kilohertz)?

Other Applications (0)

Anonymous Coward | more than 2 years ago | (#37487102)

I wonder if something like this could be used to shield a spacecraft. If an object can be made "invisible" to solar radiation (I realize this is just magnetic so far, but the technology seems to be advancing quickly) perhaps we can shield a ship well enough to make a trip to Mars feasible. At least it seems applicable to making a submarine invisible to magnetic sensors.

New material for wallets! (1)

jpvlsmv (583001) | more than 2 years ago | (#37490812)

What a great material to wrap around my credit cards when they're in my eel-skin wallet.

The eel skin has its electric field left over from its life shocking the s*** out of the fish it eats, which of course translates after death into a magnetic field that wipes the magstripe info from my credit card.

With a layer of this between them, I wouldn't have to worry about that.

And for that matter, this kind of shielding would probably wreck havoc on communications to the RFID chips on the "smart pay cards" like SpeedPass, so that people couldn't steal my money by putting a reader under the subway seat.

Hmm, now where's my patent lawyer?

--Joe

Re:New material for wallets! (1)

BJ_Covert_Action (1499847) | more than 2 years ago | (#37493218)

Maybe you should just buy a leather wallet like everyone else?

Re:New material for wallets! (1)

John.Banister (1291556) | more than 2 years ago | (#37496904)

The eel skin has its electric field left over from its life shocking the s*** out of the fish it eats, which of course translates after death into a magnetic field that wipes the magstripe info from my credit card.

MythBusters disagree [wikipedia.org]

I hate it when... (0)

Anonymous Coward | more than 2 years ago | (#37491672)

Part way through the article I see the words "If realized"... Why get my hopes up of owning my own anti-Magneto suit, just to dash them by saying that this process/device is only hypothetical? I weep silently as I sit in my chair, cursing the day I got that adamantium skeleton installed in place of my bones. -Signed, Wolverine

Nuclear subs (1)

IgnoramusMaximus (692000) | more than 2 years ago | (#37504350)

I can't believe that all of you missed the one obvious military application: concealment of nuclear submarines.

Presently nuclear subs are detectable by planes (like the P3 etc. [wikipedia.org] ) via use of magnetometers.

A sub, being a very large metal object, interferes with the Earth magnetosphere (which is for the purpose of detection a constant magnetic field) and thus can be detected an "anomaly" in the magnetic field, far above their actual location deep underwater.

This is one major weakness of modern subs that makes them detectable.

This discovery is practically custom made as a solution to this problem: to hide an object that affects a constant magnetic field.

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