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'Antimagnet' Cloak Hides Objects From Magnetic Fields
ananyo writes "Researchers have made a cloak that can hide objects from static magnetic fields, realizing a theoretical prediction they made last year. This 'antimagnet' could have medical applications, but could also be used to subvert airport security. The cloak's interior is lined with turns of tape made from a high-temperature superconductor. Superconductors repel magnetic fields, so any magnetic field enclosed within a superconductor would be undetectable from outside. But the superconductor itself would still perturb an external magnetic field, so the researchers coated its external side with an ordinary ferromagnet. The superconductor tries to repel external field lines, whereas the ferromagnet tries to draw them in — together, the two layers cancel each other out (abstract)."
"Hey, mind if I take in this superconductor cooler through the checkpoint?"
If I understand correctly, they should be able to envelope something like an MRI so that you don't have to worry about metal bits carried into the room?
Every time I start to have faith in humanity, I ruin it by driving to work between 7 and 8 am.
You could use a zillion things to subvert airport security.
Or use a private plane. Those stars don't seem to have trouble loading up private planes with all sorts of stuff.
Since metal detectors use electromagnetic waves (call those non-static magnetic fields if you want), instead of magnetic fields, that cloak wouldn't be a problem at all. Well, ok, it would cloak its interior, like any piece of conductor would. It would also trigger the alarm itself, like any piece of conductor.
But now, why are people so concerned about airport security anyway? The invention has no relation to it.
Rethinking email
Finally, a tinfoil hat replacement. Everyone knows that some aliens use magnets and not EM waves.
Because it's not "high temperature" in any sense that would be understood by the term.
It's called high temperature because it's significantly hotter than temperatures where superconductivity occurs in ordinary metals (around 30K). But even the highest temperature at which superconductivity has ever been observed is still freakin' cold... over a hundred degrees below 0
Until room temperature superconductivity is discovered (an enormous breakthrough in physics that would have countless applications), nothing's getting by airport security with this mechanism.
File under 'M' for 'Manic ranting'
So...is this something that could someday be used to protect magnetic storage media from accidental (or even deliberate) exposure to magnetic fields?
Dan Aris
Fun. Free. Online. RPG. BattleMaster.
Why is it that we have come to a point where the first thing we think of for a cool new technology application like this is "could be used to subvert airport security"??
I am sick and disgusted of where we have arrived.
I want off.
This could be a big deal in submarine warfare if they can get the temperature up. With the advent of AIP, navies are having to rely on second-string technologies like Magnetic Anomaly Detectors.
Old man story time. My Tektronix 547 CRT oscilloscope has its CRT encased in a mumetal shield. I got a powerful magnet and put it on the side of the case, the trace didn't budge at all. Great stuff. Of course, mumetal loses its properites if it's dinged, deformed or otherwise mechanically abused.
Mostly random stuff.
Currently, high temperature superconductors work up to around 100K- which is about -170C. So currently you would need a liquid nitrogen cylinder to contain the cloak and keep it cold enough. Then you would need to hide that in some other way. somehow I don't think that is likely. Room temperature superconductors are some way off- they know how low temperature (few kelvin) superconductors work, but are not sure how the high temperature conductors work- so researchers are not sure how to improve on the current designs.
Should have studied more in physics ...
Excellent! You are eminently qualified to invest in my company, which harnesses this technology to generate power from a workable perpetual motion machine!:
http://www.lhup.edu/~dsimanek/museum/unwork.htm#cheng
Terrorist Jim: Bob, we will have you wear the antimagnet cloaking suit. All we have to do is have you walk into a restroom right before you go through the scanner, open this forty gallon Thermos container and pour the liquid nitrogen all over yourself.
You'll walk to airport security and pass through the security check with no problems.
Day of the terrorist strike.
Bob enters the airport dragging a heavy carry-on suitcase. His suit is disproportionately large compared to his body, and seems quite stiff. He moves with great difficulty.
He takes his luggage into the airport restroom and enters a bathroom stall. Witnesses report a hissing noise and a strange fog coming from under the stall door. There's a splashing noise, followed by a sizzling sound and a loud wail. Bob flings open the bathroom stall to reveal his suit, bathed in vapor. Steam rises from his exposed cracked skin. He takes two steps and falls to the floor, writhing in pain, as parts of his suit shatter and skin sloughs from his hands.
Terrorist Jim (upon seeing the news reports): So next time, we strap a small refrigeration unit to Sam's back ...
Get off my virtual lawn, you damned virtual kids!
Anybody who has their own plane pretty much does whatever they want. I've landed my plane at large airports (EG: Oakland, CA) with extensive security lines for commercial flights, and driven my car out to the plane in order to load it. The only credentials I need are the keys to a plane and maybe a driver's license.
I've landed my private plane at big airports in order to hook up with commercial flights, and it's truly absurd to land, walk in off the tarmac, be personally greeted at the private aviation side of the airport, and then take a shuttle to be treated like a potential criminal in a cattle stock yard. This affords me very little respect for the TSA.
You don't need to be a Fortune 500 CEO to have a private plane, the actual cost to own (especially for a time share aka "flight club") can be similar in cost to owning a recent model car.
I have no problem with your religion until you decide it's reason to deprive others of the truth.