"Computer.........."
Posted on 05/02/2006 5:54:54 PM PDT by blam
Scientists gain insight into invisibility through a complex superlens
By Roger Highfield, Science Editor
(Filed: 03/05/2006)
The Klingons used it to make their Bird of Prey spacecraft invisible. The Romulans used cloaking too and variants of this stealth technology hid the nasty alien in the Predator films and have been mentioned in Star Wars, Doctor Who and more besides.
Scriptwriters will be pleased to discover that this science fiction idea is deemed today to be closer to science fact than we realised, according to a paper published in the Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences.
Prof Graeme Milton, of the University of Utah, and Nicolae-Alexandru Nicorovici, of the University of Technology, Sydney, announce that "we have found that cloaking might be realised". The "making of an object invisible through some cloaking device is commonly regarded as science fiction", said Prof Milton.
But with Dr Nicorovici he outlines how to do it with the help of materials with bizarre optical properties that were first postulated in 1968 by Victor Veselago, a physicist working at the General Physics Institute of the Russian Academy of Sciences in Moscow.
His work remained obscure until six years ago, when his mathematical fantasy was realised by the creation of superlenses that can make objects placed near them invisible."
When an object is bathed in light of one colour, Prof Milton and Dr Nicorovici predict that light becomes trapped near the lens and "almost exactly cancels the light incident on each molecule in the object, so it has essentially no response to the incident light. Numerically we see that the molecule is effectively invisible".
By looking through a superlens at the object "one would only see the back half of it".
How far do I trust an article that begins by alluding to Star Trek, Star Wars and Doctor Who? I'm not sure...
I'll tell you how to become invisible; Ask for a third plate of all you can eat shrimp.
Close your eyes and it's invisible as well.
So don't use a super lens and you're able to see it? Don't tell me this is a "Duh" thing.
Pictures of the invisible object:
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Ping
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I'm presuming we will see more about it when the full paper gets on the Internet
Thanks for posting this. I still have an interest in optics, although I haven't been working in the field for a couple decades. We have barely begun to understand optics, that much seems obvious.
What a waste. I could've saved him an inordinate amount of time by selling him my car. Once it's on the road it apparently becomes invisible to all other drivers.
Way cool dude, way cool.;)
In other words - In real life, a large collection of said molecules are just as visible as always.
Wow, how'd you do that?
Clinton used to make his pants disappear.
The making of an object invisible through some cloaking device is commonly regarded as science fiction. But we have found that cloaking might be realized. Specifically, regions of anomalous localized resonance, such as occur near superlenses, are shown to lead to cloaking effects. This occurs when the resonant field generated by a polarizable line or point dipole acts back on the polarizable line or point dipole and effectively cancels the field acting on it from outside sources, so it has essentially no response to the external field. Numerically and analytically we see that the polarizable line or point dipole is effectively invisible to the external time harmonic field. Cloaking is proved in the quasistatic limit for finite collections of polarizable line dipoles that all lie within a specific distance from a coated cylinder having a shell dielectric constant close to -1 and a matrix and core dielectric constant close to 1. Cloaking is also shown to extend to the Veselago superlens outside the quasistatic regime: a polarizable line dipole located less than a distance d/2 from the lens, where d is lens thickness, will be cloaked due to the presence of a resonant field in front of the lens. Also a polarizable point dipole near a slab lens will be cloaked in the quasistatic limit. The hope of using cloaking to see the interior of an object by making half of it invisible remains an intriguing possibility. This is joint work with Nicolae Nicorovici.
OK, so everybody, please join me in nodding your heads like we actually understood that. Adding a pensive sounding "hmmmmm"; five bonus points.
"De Selby, noting that light takes a portion of time, however small, to reach its target, came upon the idea that if a network of mirrors were aligned properly a viewer could actually see into the past through a series of repeated reflections:
What he states to have seen through his glass is astonishing. He claims to have noticed a growing youthfulness in the reflections of his face according as they receded, the most distant of them -- being the face of a beardless boy of twelve, and, to use his own words, ‘a countenance of singular beauty and nobility’.”
Scotchlite reflective film, used for traffic signs and other reflective markings, gets its reflective properties from the thousands of glass beads that are embedded in every square foot of the stuff. Perhaps a film with a similar content of the specified "invisible" lenses, able to be activated (somehow) at the skipper's command, would make a ship invisible. 'Course, it would also need a way to hide from radar and laser detection, or magnetic, for that matter. Probably we're not quite to Klingon technology yet.
I'll tell you how to become invisible; Ask for a third plate of all you can eat shrimp.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Shoney's used to run an all you can eat fried shrimp special. I knew a 300 pounder who used to brag that he was asked to leave on condition that he did not have to pay the bill if he would just stop ordering more. He was a bottomless pit.
That works every time.
I had a few motorcycles like that.
Probably we're not quite to Klingon technology yet.
Thanks for the laughs- I had several bikes, a red one-ton wrecker, and currently a Sunburst Orange SUV that all suffered from that "Honey, you forgot to turn off the Klingon Cloaking Device again" syndrome.
The only bike I had that seemed to be visible was the 1979 FLH – the same model used by police. I wore a white half shell that added to the effect.
I always wore a yellow "Mooneyes" wind breaker from Dean Moon's outfit, in the hopes it would help, and had "John" embroidered on the back to personalize it.
Still didn't seem to make me visible.
I had a 1957 74, that was a police bike- hard tail, rocker clutch, sideshifter. Small fatbobs, for some reason. I liked the bloody thing, but it sure pounded the bejabbers out of you on rough roads.
The "superlens" effect that they're talking about is described here.
The impression I get is that they are not talking about "cloaking" of anything bigger than micro- or molecular-scale
The only subject that reporters are more useless in covering is Religion. It's like those cavemen/apes in the movie "2001: A Space Odessy" trying to figure out the monolith; hitting it with sticks, screaming at it, jumping up and down...
It's perfectly understandable to me. But then I always was interested in tadpoles wearing coats and polarized lenses (especially aviator style)
I had a 1957 74, that was a police bike- hard tail, rocker clutch, sideshifter. Small fatbobs, for some reason. I liked the bloody thing, but it sure pounded the bejabbers out of you on rough roads.
An invisible person? Boy would I like to see that!
"Computer.........."
Excellent. It seems to work quite well!
"What a waste. I could've saved him an inordinate amount of time by selling him my car. Once it's on the road it apparently becomes invisible to all other drivers."
You want invisible, try riding a motorcycle on the road. Most drivers don't seem to be able to see us, despite the always-on headlight, colorful garb and helmet, etc. They'll pull out in front of you every time if given a chance.
There was an article posted to FR a while back about the superlens. This is a substance with a negative refractive index. When light passes into a more dense substance, it is refracted (or bent) towards the normal (perpendicular line) to the surface. A material with a negative refractive index would have the opposite behavior. Light passing into would be bent away from the normal, as if the material were less dense than vacuum.
In that article, it talked about possible applications for resolving objects at a resolution smaller than the wavelenght of visible light. Visible light is what, 400-700 nanometers, and the article you posted saus they have imaged objects as small as 40 nanometers.
I don't understand how you would "cloak" something, but it sounds like establishing some sort of destructive interference.
We had a carpool in California from Simi Valley to the V.A. hospital (Wadsworth) in W. L.A.; two of the members were canteen officers who went over 250 pounds each.
Many's the time they would regale us with their tales of being thrown out of those buffets, it is almost a sport with some guys.
Yes, those old 74's would make a man out of you- or kill you in the attempt.
What I liked was the manual spark retard- you could induce backfires at will, and it worked wonders on bike-chasing dogs...
What I liked was the manual spark retard…
I believe it was the "Romulan Bird of Prey", not Klingon.
The abstract says "Specifically, regions of anomalous localized resonance, such as occur near superlenses, are shown to lead to cloaking effects. This occurs when the resonant field generated by a polarizable line or point dipole acts back on the polarizable line or point dipole and effectively cancels the field acting on it from outside sources, so it has essentially no response to the external field.
The way we "see" things is that light impacts on an object's surface and is either absorbed or reflected, and we see the reflected/re-emitted light. The impression I get from the abstract is that a (presumably nano-scale) object, when put into a resonant state, has light passing thru the space it occupies without the incident light interacting with the object.
LOL!
As I recall ( God, it's been over 30 years... ) I'd ease it past TDC with the ignition off, then switch on, so the pistons would be accelerating toward top for the first spark when you stood on the pedal.
Still kicked the snot out of me occasionally.
Ah! Voice recognition software. I had forgotten that one. Thanks for reminding me.
Still kicked the snot out of me occasionally.
Now and then – particularly if I was in a hurry or distracted. Lovely women were (and are) tremendous distractions.
"LICK" engine through?
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