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When water from a stream encounters a rock, it bypasses and resumed his
route as if nothing had happened. Downstream, impossible to know if
that particular molecule is passed directly, or if they have avoided
the rocks. The cloak of invisibility basically follows this principle.
The object (the rock in our example) is covered with a material with
electromagnetic properties carefully calculated so that the waves that
penetrate the inside spread in the envelope before resuming their
journey in a straight line behind. A "meta-material" as the researchers
say that, somehow, will bend the waves as the water around the rock.
Since 2006, many teams rush to advance the discipline. With a double
objective. Find the right combination to develop an effective
meta-material with visible light, to realize the myth of Harry Potter,
and most importantly, able to maintain its properties in a wide range
of frequencies: there is no point of being invisible in yellow, if it
is not in the red! In 2008, a French team had offered his recipe of
meta-materials, and works in manufacturing (2). But the task is
arduous. For if the simulators were used to model behavior with the
finesse of materials on paper, developing an effective is not easy.
It is precisely in this direction have worked Smith and Jun Cui, who
claims to have manufactured their cloak ten days. Interrogated in
columns of Technology Review, the magazine of the Massachusetts
Institute of Technology, John Pendry (Imperial College , Great Britain)
s'avoue surprised by the speed at which the first invisibility cloak
broadband has been developed. And he knows whereof he speaks: it Pendry
who laid the theoretical foundations of the cloak of invisibility, and
he had proposed only a year ago for a runway theoretical capes broad
spectrum. "I was expecting not progress as fast as experimental. " The
device of Smith and Jun Cui is rectangular, 50 cm by 10 cm, with a
thickness of one centimeter. It is covered six hundred items of copper
in the form of I.
Pending any hidden object, which would make the business of the
military if it were possible, the scope of invisibility cloaks is
immense. Although a clever man could predict their applications. But we
can already devices to improve the performance of solar cells, lenses
for unmatched resolutions for biology, physics, and photography. Tech
Review points out that Nicholas Fang already using hyper-lenses able to
see how internal cells. Meanwhile, it will monitor the performance of
many teams that are thrown into the adventure. Because in terms of
invisibility cloaks, the results are visible immediately ....
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