RE: [ufodiscussion] Invisibility Shields Planned By Engineers
- Do you really think this information would be out if they didn't have it
From: Light Eye [mailto:universal_heartbeat2012@...]
Sent: Tuesday, March 01, 2005 2:08 AM
To: Global_Rumblings@...; SpeakIt@...;
Subject: [ufodiscussion] Invisibility Shields Planned By Engineers
Love and Light.
Invisibility Shields Planned by Engineers
James Owen in London
for National Geographic News
February 28, 2005
In popular science fiction, the power of invisibility is readily apparent.
Star Trek fans, for example, know that the devious Romulans could make their
spaceships suddenly disappear.
But is the idea really so implausible? Not according to new findings by
scientists who say they have come up with a way to create cloaking device.
Electronic engineers at the University of Pennsylvania in Philadelphia are
researching a device they say could make objects "nearly invisible to an
observer." The contrivance works by preventing light from bouncing off the
surface of an object, causing the object to appear so small it all but
The concept was reported today by the science news Web site news@....
It says the proposed cloaking device would not require any peripheral
attachments (such as antennas or computer networks) and would reduce
visibility no matter what angle an object is viewed at.
Sir John Pendry, a physicist at Imperial College, London, said the concept
potentially holds several important applications "in stealth technology and
While types of invisibility shielding have been developed before, the
phenomenon described by Andrea Alú and Nader Engheta sounds like something
that might have been witnessed from the bridge of science fiction's starship
The concept is based on a "plasmonic cover," which is a means to prevent
light from scattering. (It is light bouncing off an object that makes it
visible to an observer).
The cover would stop light from scattering by resonating at the same
frequency as the light striking it. If such a device could cope with
different wavelengths of electromagnetic radiation (including visible
light), in theory, the object would vanish into thin air.
Alú and Engheta investigated experimental plasmonic covers that incorporated
metals, such as gold and silver, to hide visible light.
When light strikes a metallic material, waves of electrons, called plasmons,
are generated. The engineers found that when the frequency of the light
striking the material matched the frequency of the plasmons, the two
frequencies act to cancel each other out.
Under such conditions, the metallic object scattered only negligible amounts
The researchers' studies show that spherical and cylindrical objects coated
with plasmonic shielding material produce very little light scattering.
These objects, when hit by the right wavelength of light, were seen to
become so small that they were almost invisible.
The study is supported by the U.S. Defense Advanced Research Projects
Agency, which researches and develops cutting edge military technology.
Some experts note, however, that cloaking devices that could enable military
vehicles and aircraft, let alone spaceships, to become completely invisible
to the enemy are likely to remain elusive for the foreseeable future.
John Pendry, the Imperial College physicist, said that light-shielding
covers would have to be customized to match the properties of each and every
object they hide.
It would be still more difficult to devise shields that could cope with all
wavelengths of the visible spectrumfrom red to violet lightand not just a
Types of invisibility shielding previously proposed by scientists depend on
advanced camouflage systems, rather than objects being made to look
undetectably tiny. Such systems involve light sensors that create a mirror
image of the background scene on the concealed object.
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Despite the exciting possibilities raised by the new research, it may take
us some time before science is able to catch up with those evasive Romulans.
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