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Плащ Невидимка к середине 21 века

 
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shamil
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Joined: 21 Nov 2005
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PostPosted: Mon Oct 30, 2006 12:04 am    Post subject: Плащ Невидимка к середине 21 века Reply with quote

Ниже приводится статья, опубликованная в осеннем номере журнала Focus.

Professor Sir John Pendry, theoretical physicist, Imperial College London answers our questions.

How did you get into the area of invisibility?
About ten years ago I was doing some work for Marconi on material absorbed radar wavelength, made of long stands of carbon fiber. This made me think that there could be a whole class of new materials, which we later called metamaterials, with properties that are to do with their structure rather than what they are made of.

Where did you go from there?
Marconi told me to go way for a while and think about what else you might be able to do with this kind of material.

And what sort of think did you come up with?
We came up with the materials that had a negative magnetic response and a negative electrical response. This let on to the idea that we could made something with the negative refractive index, which would mean we’d be able to manipulate the light. Invisibility is just of the outcomes.

Were you the first to do this?
A Russian scientist, Victor Veselago, had done some of the theoretical work before, but he never came up with a possible material, whereas we did.

What was the reaction to your work?
We had quite a battle to get it accepted. At first, some physics thought that negative refraction was impossible because that’s what had always been taught.

What is metamaterial?
Metamaterial is based on tiny metal structure embedded on the surface of its non-metallic structure. There structures mimic the way atoms interact with light and are tuned so the photon skims around the edge of material. To ensure that the path of the light ray is maintained from any direction around an object, the metamaterial has to be arranged exactly. Any movement of the material will introduce distortion in the light passing trough it. This means that the material has to be rigid – it’s an invisible shield rather than a cloak. The range of wavelength that a metamaterial screen can channel is determined by its depth. A shallow screen would only be invisible to a narrow range of wavelengths, a deeper one would be invisible to entire visible spectrum, and thicker one still would be invisible to infrared or ultraviolet wavelength as well.

History on Hiding
390BC – Plato includes the fable of the Ring of Gyges in his work The Republic. The ring makes the wearer invisible, but also corrupts.

1860s – Stage magicians invent "the formula for invisibility", using mirrors to hide an assistant inside an apparently empty cabin.

1875 – Illusionist Max Auzinger develops "the black art": in low light, assistant dressed in black becomes "invisible" against a black velvet screen.

1897 – In his novel The Invisible Man, HG Wells attempts to describe a scientific basis for invisibility, using the model of an altered refractive index.

1942 – Project Yehudi, a US Navy attempt to make aircraft invisible. Lights illuminate the plane to give it the same brightness as the sky above, drastically reducing visibility.

1967 – Russian physicist Victor Veselago predicts the existence of a material with a negative index of refraction, termed "left-handed".

1982 – The F117 Nighthawk stealth fighter enters service, made invisible to radar with shaping and radar absorbent material.

1994 – The US Army launches its "Invisible Soldier" program to "make the soldier invisible to the electromagnetic spectrum".

2001 – First demo of material with a negative refractive index by a team of University of California, San Diego.

2003 – Professor Susumu Tachi of Tokyo University demonstrates an "indivisible cloak", onto which an image of the scene behind is projected.

2005 – A metamaterial "superlens", more powerful than a conventional lens, is demonstrated at Berkeley, California, proving the capabilities of metamaterials.

2006 – John Pendry of Imperial College, along with David Smith and David Schuring at Duke University in North Carolina, publish the theory for a metamaterial "invisible cloak".

2008 – First metamaterial for shielding objects from radar is expected to be demonstrated at Duke University in North Carolina.

2011/2016 – First metamaterial for making objects completely optically invisible is likely to be produced.
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shamil
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PostPosted: Mon Nov 13, 2006 3:36 pm    Post subject: Reply with quote

В русскоязычных СМИ данный вопрос также начали освещать - rambler.ru/news/science/0/9086708.html
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