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My dream of gaining superpowers moves closer to reality!

 

From the New York Times:

 

SCIENTISTS CREATE 'CLOAK OF INVISIBILITY'

 

WASHINGTON (AP) -- Scientists are boldly going where only fiction has
gone before -- to develop a Cloak of Invisibility. It isn't quite ready
to hide a Romulan space ship from Capt. Kirk or to disguise Harry
Potter, but it is a significant start and could show the way to more
sophisticated designs.

In this first successful experiment, researchers from the United States
and England were able to cloak a copper cylinder.

It's like a mirage, where heat causes the bending of light rays and
cloaks the road ahead behind an image of the sky.

''We have built an artificial mirage that can hide something from
would-be observers in any direction,'' said cloak designer David
Schurig, a research associate in Duke University's
<http://topics.nytimes.com/top/reference/timestopics/organizations/d/duk
e_university/index.html?inline=nyt-org>  electrical and computer
engineering department.

In this case, researchers used microwaves to try to detect the cylinder.
Like light and radar waves, microwaves bounce off objects, making them
visible to instruments and creating a shadow that can be detected.

Cloaking differs from stealth technology, which does not make an
aircraft invisible but reduces the cross-section available to radar,
making it hard to track.

Cloaking simply passes the radar or other waves around the object as if
it weren't there, like water flowing around a smooth rock in a stream.

The new work points the way for an improved version that could hide
people and objects from visible light.

Conceptually, the chance of adapting the concept to visible light is
good, Schurig said in a telephone interview. But, he added, ''From an
engineering point of view it is very challenging.''

The cloaking of a cylinder from microwaves comes just five months after
Schurig and colleagues published their theory that it should be
possible. Their work is reported in a paper in Friday's issue of the
journal Science.

''We did this work very quickly ... and that led to a cloak that is not
optimal,'' said co-author David R. Smith, also of Duke. ''We know how to
make a much better one.''

The first working cloak was in only two dimensions and did cast a small
shadow, Smith said. The next step is to go for three dimensions and to
eliminate any shadow.

Viewers can see things because objects scatter the light that strikes
them, reflecting some of it back to the eye.

''The cloak reduces both an object's reflection and its shadow, either
of which would enable its detection,'' Smith said.

The device is made of metamaterials, mixtures of metal and circuit board
materials such as ceramic, Teflon or fiber composite.

Looking at a cloaked item, Smith said, ''One would see whatever is
behind the cloak. That is, the cloak is, ideally, transparent. Since we
do not have a perfect cloak at this point, there is some reflection and
some shadow, meaning that the background would still be visible just
darkened somewhat. ... We now just need to improve the performance of
cloaking structures.''

Redirecting electromagnetic waves also could prove useful in protecting
sensitive electronics from harmful radiation, Smith said. 

In a very speculative application, he added, ''one could imagine
'cloaking' acoustic waves, so as to shield a region from vibration or
seismic activity.''

Natalia M. Litchinitser, a researcher at the University of Michigan
<http://topics.nytimes.com/top/reference/timestopics/organizations/u/uni
versity_of_michigan/index.html?inline=nyt-org>  department of electrical
engineering and computer science who was not part of the research team,
said the ideas raised by the work ''represent a first step toward the
development of functional materials for a wide spectrum of civil and
military applications.''

Joining Schurig and Smith in the project were researchers at Imperial
College in London and SensorMetrix, a materials and technology company
in San Diego.

The research was supported by the Intelligence Community Postdoctoral
Research Fellowship Program and the United Kingdom Engineering and
Physical Sciences Research Council.

 


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