You're right. Let's ping him!
Posted on 07/31/2006 11:25:04 AM PDT by AntiGuv
LONDON (Reuters) - It's unlikely to occur by swallowing a pill or donning a special cloak, but invisibility could be possible in the not too distant future, according to research published on Monday.
Harry Potter accomplished it with his magic cloak. H.G. Wells' Invisible Man swallowed a substance that made him transparent.
But Dr Ulf Leonhardt, a theoretical physicist at St Andrews University in Scotland, believes the most plausible example is the Invisible Woman, one of the Marvel Comics superheroes in the "Fantastic Four."
"She guides light around her using a force field in this cartoon. This is what could be done in practice," Leonhardt told Reuters in an interview. "That comes closest to what engineers will probably be able to do in the future."
Invisibility is an optical illusion that the object or person is not there. Leonhardt uses the example of water circling around a stone. The water flows in, swirls around the stone and then leaves as if nothing was there.
"If you replace the water with light then you would not see that there was something present because the light is guided around the person or object. You would see the light coming from the scenery behind as if there was nothing in front," he said.
In the research published in the New Journal of Physics, Leonhardt described the physics of theoretical devices that could create invisibility. It is a follow-up paper to an earlier study published in the journal Science.
"What the Invisible Woman does is curve space around herself to bend light. What these devices would do is to mimic that curved space," he said.
Although the devices are still theoretical, Leonhardt said scientists are making advances in metamaterials -- artificial materials with unusual properties that could be used to make invisibility devices.
"There are advances being made in metamaterials that mean the first devices will probably be used for bending radar waves or the electromagnetic waves used by mobile phones," he said.
The devices could be used as protection mechanisms so the radiation emitted from mobile phones does not penetrate electronic equipment. It is guided around it.
"It is very likely that the demonstration for radar would come first and very soon. To go into the visual will take some time but it is also not so far off," Leonhardt said.
the faceted diamond is one solution, essentially analogous to planar mirror surfaces which never present a useful angle of reflection.
the aplanar curve is another solution, analogous to a mirror surface which spreads the angle of reflection to a maximally diffuse (ie: weak) range, producing a very small and vague signal return.
the copper mesh and carbon-fiber materials both planes use to absorb some RF is yet a third solution.
the grids covering the intakes on the F117 is a fourth solution - the grid size allows RF to enter, but not to reflect.
don't assume so much.
You're right. Let's ping him!
Better graphics at MSNBC article
Essentially, you can have a material that bends light around what you want to conceal
LOL.
The word "antenna" may be inaccurate, but there's something else stealth technology than shape. You're parroting the "official story" without analysis.
see post 46
supposition: "antenna" = "the copper mesh and carbon-fiber materials both planes use to absorb some RF is yet a third solution."
remember that a receiving antenna converts RF into electricity and heat. iirc, that is what the copper mesh in the stealth material does. this would effectively make a hole in the signal strength, and a void in the return signal.
*grins*
Ah figger'd et flow'd better'n "Ah'm f'um Missouri... DON'T show me!"
I should be eligible for a discount.
thanks for all.
iirc, some hints of this were published a month or so back.
againiirc, the weight and power requirements of the devices seem likely to limit application to heavy vehicles and stationary installations.
Which reminds me, didja know that you can get "Soap" on CD through Netflix?? They have all of the seasons...
Lol... again.
Ok. It wont let me post this, so I'll have to post it in two pieces. Hope that's ok. If I try to quote, it only allows the quote, and not the reply.
I was a Naval Electronic Warfare Technician. I was going by what you said. Antennae can either radiate or receive. If they are radiating, then they can be detected. If they are merely receiving, then they can take no action on the signal that they are receiving. That's all that I was saying.
strangely enough used to happen to me when i drank...the new tool on the war on terror...LOL
When we were in the shipyards and had the AN/WLR-1 tuners rebuilt, we went to sea with a lady tech to check the system out. All that she cared about was whether we could pick up "All My Children". She listened intently. Worked fine. Naturally, we checked the system out fully once she was off of the ship. Union labor, gotta love it.
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