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How To Cloak Objects At a Distance
KentuckyFC writes "All invisibility cloaks to date work by hiding an object embedded inside them. Now a group of physicists have worked out how to remotely cloak objects that sit outside a cloaking material. The trick is to make the cloaking material with optical properties that are exactly complementary to the space outside them. Complementary means that the material reverses the effect the space has on a plane wave of light passing through it. To an observer this space would appear to vanish. The scientists say that to cloak an object sitting outside the cloaking material, first measure its optical properties and then embed a "complementary image" of the object within the cloak. So a plane wave is first distorted by the object but then restored to a plane by the complementary image of the object within the cloak (abstract). An observer sees nothing. This method has another benefit. Objects hidden in conventional cloaks are blinded because no light enters the cloaked region. But objects that are remotely cloaked like this should still be able to see their surroundings."
You'll know when cloaking is really working when the monthly dupe of "cloaking, this time for real" stops showing up here.
"The trick is to make the cloaking material with optical properties that are exactly complementary to the space outside them. "
So if you are hiding a tank in the desert, paint it desert colors?
Oh wait more complex... desert != shiny...
use flat paint.
got it!
Do not look at laser with remaining good eye.
You'll know when cloaking is really working when the monthly dupe of "cloaking, this time for real" stops showing up here.
Because they managed to cloak the article?
The better question is, can they fire while cloaked? I hear the Klingons made substantial advances in that area.
"Gee, if we had enough money, we could make your troops invisible, Mr. General Sir."
The simple truth is that interstellar distances will not fit into the human imagination
- Douglas Adams
Wouldn't pr0n constitute a complimentary image? Cuz I gotta tell ya with the right pr0n nearly everything around it disappears.
Everyone knows that a tachyon sub-space burst from the main deflector dish invariates the sublimated inverse proportional fields that all cloaking devices use.
Phase the array with multi-numinal values and any cloak in the perimeter will be dropped due to subversive nominal decay but only if you attune your tertiary sensing systems to compensate for the quadralinear flux.
This is all so simple, and I have to wonder about the credentials of /. editors that would post such elementary issues on this website.
I mean really, this is first trimester stuff that any recruit can do off the tops of their heads.
How hard can it be if even girls manage it?
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
Ummm...howzabout just hiding behind a tree or ducking...
This technology, if adopted by the military, will probably only be useful against civilians. Against another sophisticated military there will always be a way to detect what you're trying to hide through other means than visible light - magnetism/alterations in the earth's magnetic field (in the case of big chunks of metal, heat), RF emissions, overhead imaging, radar, sonar, etc.
You won't be able to hide your tank like this, but the small laser turrets to keep the neighbor's cat off the lawn might work... now if only those sharks would stop swimming.
Seven puppies were harmed during the making of this post.
Notquitecajun, will you stand up please. (gunshot)
This demonstrates the value of not being seen.
I am officially gone from
Wile E. Coyote claims prior art.
Support Right To Repair Legislation.
I'll go you one better - over in the Middle East, there were apparently some insurgents/terrorists/whoever using the tried-and-true method of hiding in a sandstorm before attacking or while attacking. It worked well in the good old days, but we now have these things called satellites and night-vision and infrared and technology, where they're pretty much sitting ducks now.
And here I always thought that explaining a joke was sure to ruin it.
... in your argument is "against another sophisticated military".
However this is rarely the case. Nowadays most engagements the US Military is involved in are against people with little more than 25-50 year old weapons. The problem the US Military has is the on the ground war against these kinds of insurgents - this tech. would be invaluable against them, you could approach a camp on foot without fear of being seen.
Well, no, actually they take a photo of the subject, make a sort of translucent negative, and put it in front of the object and make the object disappear from view. Slightly more ingenious because the background can change.
Not sure how they handle the "light behind the 'cloaked object' isn't shining through it" scenario. Presumably you could bend the light around the object and back into it's orignal path - but that's the 'embedded cloaking device' as far as I can tell.
Scientists are looking in the wrong direction in this matter. Like in so many other breakthroughs, they just have to watch how nature does it. What in nature can be totaly invisble without any kind of complex technology or huge power consumption? Easy: keys.
I'd like to see your source on that one, Assuming that sound can't move through the rest of the rifle(for sake of discussion) and will only escape out of the muzzle the shooters ear is about 1 meter away form the source. The Barrett M82 (using .50 BMG round) has a max effective range of 6800m with a muzzle velocity of 853 m/s. That means that it will take that round 7.79 seconds to go the max distance or 2.16 seconds to go the effective range of 1850 meters.
The speed of sound is 340.29m/s, so for the sound of the gun shot to go from the muzzle to the shooters ear 1 meter away will take apx 0.0029 seconds.
At 853 m/s the round will have only traveled 2.47 meters away from the muzzle.
Provided the target is less than 2.47 meters away then yes the will have a whole in them before you the shooter hears teh shot, but you said thousands of yards, which as we proved is just wrong. Now had you said that you the target will have a whole in you before you the target even hears the report then yes you would be right.
Oh and you totally misused the joke anyway of th GP. It was a Monty Python sketch. /All figures from GIS and wikipedia) //Math could be wrong, please correct me if I'm wrong
500 dollar reward for tip(s) leading to the arrest of the person(s) who stole my sig.
You do realize you will be blind, right?
Unless you poke some holes in your cloak, and then people will just see eyes floating in the air.
Actually, that seems like a fantastic idea. Sign me up!
Okay so that's one invisibility cloak for...Mr Anonymous Coward.
I understand that using feminine pronouns is the politically correct thing to do, but in the context of this sentence I think it's fair to assume that the engineer in question is most likely male.