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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
As much as I love the Father Ted reference, that really doesn't have anything to do with this article.
They should be working on the SEP field.
Hitchikers guide reference:
"The technology required to actually make something invisible is so complex and unreliable that it isn't worth the bother. The Somebody Else's Problem field is much simpler and more effective, and can be run for over a hundred years on a single torch battery. This is because it relies on people's natural predisposition not to see anything they don't want to, weren't expecting, or can't explain."
You don't even need a battery. Just build it to look like a sink full of dirty dishes in a student household and no one will see it.
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!
Scientists: "We've made an invisibility cloak that will make your soldiers vanish!"
General: "That's amazing, let's try these out."
Scientists: "Right, Here is one you can try, but if you want more then we need money... a lot of money."
General: "Sorry, the deals off, the soldiers say they can't see out of it when they're inside it."
Scientists: "Give us a few minutes."
[Obligatory view of shed with hammering and sawing noises]
Scientists: "Okay, how about your troops just hide behind it?"
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.
no, because then you're behind/inside the cloak and your visibility in the cloaked direction is zero. you're not unbending the light with a complementary image. if the light source is behind you, you'd just look like a jackass holding up a bed sheet.
the method proposed in the article is to hide objects outside (hence, "How to Cloak Objects At a Distance") of a cloak using a complementary material. no materials have yet been developed to do this.
it doesn't even necessarily have to be a physical material. if you can use lasers or an EM field to bend(or unbend) light back to its original state, then you can simulate a virtual complementary material. you'd still need to determine the optical properties of the object that you want to cloak to create the complementary image, but you could theoretically create a mobile/non-stationary cloaking device this way.
I dunno, they've got a good point. If no light is getting in to the object being cloaked, then it's not just invisible, it's blind...so while you wouldn't see much in the Sorority Girls' dorm, you could have loads of laughs feeling up anything that crossed your path.
This, then, shall be your test. To the engineer who can build her own invisibility cloak, I say that she is worthy of raiding the Sorority Girls' dorm. To all those who dare not face the challenge, their punishment shall be downloading pr0n.
"The biggest problem with communication is the illusion that it has taken place."
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.
Well, if they're hiding in the sandstorm BEFORE the attack, sure.
But during? You'll be hard pressed to find a radio wave length that'll cut through what is essentially a huge but very fluffy stone and NOT cut through humans (tiny bit of water in the middle). Infrared will be blurred out. Radar will too.
What kind of advances have the military conjured into being that'll see through a sandstorm and tell you what's inside it (outside of lots and lots and lots of sand)?
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.
It's not just the school systems that frown upon non-standard answers, it's the majority of society. In many situations, propose an idea even slightly outside of the predominant group-think, and watch how many folks start to get offended/shoot it down without thought.
For example - I had a boss write a simple VB app that cut the time needed for his subordinates to do a specific task by at least 50% every time, sometimes as much as 80%, while improving the quality of the output. His boss shot it down and prohibited its use because my boss wasn't assigned to write software, and they had paid someone else to write less-effective software that used more bandwidth and provided a lower quality output.
In another case, we had a door clearance problem in a customer area due to carpet installation. Funding for a new door wasn't forthcoming, so a couple of us on the late shift lowered the false floor just enough to regain clearance. We didn't think much of it, since it solved the problem without needing any funding. However, that solution got a lot more attention (both negative and positive) than we expected. All of the regular visitors noticed. Some folks thought it was a great idea. Those responsible for the building bristled at the idea of a non-standard solution when we suggested it (after the fact, and played it off as a joke when we saw their response), so we had to tell them we bought a new door out of our own funds. (I guess spending hundreds of dollars on a new door is more acceptable than a few radians of rotation of a few large bolts in their eyes.)
Despite all of the feel-good seminars, I believe people in general still aren't accepting of ideas outside of their limited fields-of-view. If I recall correctly, in Japan, there is a saying that roughly translates to "The nail that sticks up is hammered down." Although U.S, citizens like to say that the saying does not apply to them, and individuality is encouraged, I think that the saying is applicable in many U.S. situations as well.
I hope that most reading this work for those without such a limited field of view. It is so much more enjoyable to go to work with bosses that encourage thinking.