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The Raelian Movement
for those who are not afraid of the future : http://www.rael.org
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4 November 2010 Last updated at 00:11 GMT
http://www.bbc.co.uk/news/science-environment-11686303
Invisibility cloak closer with flexible 'metamaterial'
By Jason Palmer Science and technology reporter, BBC News
Scientists in the UK have demonstrated a flexible film that represents
a big step toward the "invisibility cloak" made famous by Harry
Potter.
The film contains tiny structures that together form a "metamaterial",
which can, among other tricks, manipulate light to render objects
invisible.
Flexible metamaterials have been made before, but only work for light
of a colour far beyond that which we see.
Physicists have hailed the approach a "huge step forward".
The bendy approach for visible light is reported in the New Journal of Physics.
Metamaterials work by interrupting and channelling the flow of light
at a fundamental level; in a sense they can be seen as bouncing light
waves around in a prescribed fashion to achieve a particular result.
But light waves can only be herded around by structures about the size
of their wavelength - a property which is connected to their colour.
Until now, the most striking demonstrations of invisibility have
occurred for light waves with a much longer wavelength than we can
see. This is because it is simply easier to construct metamaterials
with relatively large structures.
Even flexible metamaterial films have been shown off for this
high-wavelength range.
For the far shorter waves we can see, a metamaterial requires
structures so tiny - nanostructures - that they push the boundaries of
manufacturing.
"The first step is imagining first of all that this could be done,"
said Andrea Di Falco of St Andrews University, the author of the
paper.
"All the typical results have been reached in flat and rigid surfaces
because this is the legacy of the procedures used to create
nanostructures."
So instead of building the typical stacks of the "fishnet" structures
on hard, brittle silicon, Dr Di Falco used a thin polymer film.
"Typically what you do is stack several layers of fishnet structures
and this all together will give you a metamaterial," Dr Di Falco
explained.
"What I've done here is fabricate a single layer - I lift it off so
that at the end I am left with a self-standing membrane - and show
that it has the properties required to create a 3D flexible
metamaterial."
Tents moment
Ortwin Hess, a physicist who recently took up the Leverhulme Chair in
Metamaterials at Imperial College London, called the work "a huge step
forward in very many ways".
"It clearly isn't an invisibility cloak yet - but it's the right step
toward that," he told BBC News.
He added that the next step would be to characterise the way that the
material's optical properties change as it is bent and folded.
If the properties were sensitive to the movement, it may be useful for
next-generation optics and lenses in, for example, handheld cameras.
If instead they were impervious to bending and motion, the
invisibility cloak could be that much closer - but Professor Hess
added that is still some way off.
"Harry Potter has to wait still - that's the huge goal," he said.
"So far he's had to live in a house and now he can live in something
like a tent; it's not the cloak that adjusts to his shape, but it's a
bit more flexible. Now we have to take the next step forward."
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WARNING FROM RAEL: For those who don't use their intelligence at its full
capacity, the label "selected by RAEL" on some articles does not mean that I
agree with their content or support it. "Selected by RAEL" means that I believe
it is important for the people of this planet to know about what people think or
do, even when what they think or do is completely stupid and against our
philosophy. When I selected articles in the past about stupid Christian
fundamentalists in America praying for rain, I am sure no Rael-Science reader
was stupid enough to believe that I was supporting praying to change the
weather. So, when I select articles which are in favor of drugs, anti-semitic,
anti-Jewish, racist, revisionist, or inciting hatred against any group or
religion, or any other stupid article, it does not mean that I support them. It
just means that it is important for all human beings to know about them. Common
sense, which is usually very good among our readers, is good enough to
understand that. When, like in the recent articles on drug decriminalization, it
is necessary to make it clearer, I add a comment, which in this case was very
clear: I support decriminalizing all drugs, as it is stupid to throw depressed
and sad people (as only depressed and sad people use drugs) in prison and ruin
their life with a criminal record. That does not mean that there is any change
to the Message which says clearly that we must not use any drug except for
medical purposes. The same applies to the freedom of expression which must be
absolute. That does not mean again of course that I agree with anti-Jews,
antisemites, racists of any kind or anti-Raelians. But by knowing your enemies
or the enemies of your values, you are better equipped to fight them. With love
and respect of course, and with the wonderful sentence of the French philosopher
Voltaire in mind: "I disapprove of what you say, but I will defend to the death
your right to say it".
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"Ethics" is simply a last-gasp attempt by deist conservatives and
orthodox dogmatics to keep humanity in ignorance and obscurantism,
through the well tried fermentation of fear, the fear of science and
new technologies.
There is nothing glorious about what our ancestors call history,
it is simply a succession of mistakes, intolerances and violations.
On the contrary, let us embrace Science and the new technologies
unfettered, for it is these which will liberate mankind from the
myth of god, and free us from our age old fears, from disease,
death and the sweat of labour.
Rael
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