Invisibility is
no longer looking quite so impossible.
In fact that last about special antennas screams for a Nano printed
surface like a physical cloak. Advancing electronic technology will bring this
all long rather quickly also.
Invisibility on
the battle field makes it completely untenable even if you are operating from a
position of parity. In fact it makes
warfare already effectively obsolete, truly obsolete. Standoff saturation becomes the only meaningful
way to punish.
It has also been
pretty clear for a long time that non-human craft have been operating in our
skies for a long time moving in and out of long established Earth bases. They are all cloaked and only rarely become
uncloaked. Even that first report in
1947 hinted strongly at cloaking.
It obviously is
not perfect but certainly good enough to leave us with mostly lights in the sky
and scant really good daytime observations.
We're Getting
Really Close to Making a Superpower Reality
Ever want to be invisible? It could happen soon in
America, unless Canada beats us to it.
The greatest hypothetical question of all time may
be one step closer to being answerable. No, no one has yet invented a horse-sized duck or a thousand duck-sized horses. I'm
talking about the greatest hypothetical question:flight or invisibility?
Experiencing something approaching human flight has
long been possible. For a price, anyone can leap out of a plane with a
parachute, and jetpacks can make up the difference. As for the
second, more elusive part of the equation? Researchers from Texas and Toronto
say they have invented two different types of invisibility cloaks. For now,
these devices only make things seem to disappear on wavelengths undetectable to
the human eye, but researchers on both products say a full-scale invisibility
cloak is no longer just an impossible dream.
While the allure of the power of invisibility goes
back at least as far as H.G. Wells' The Invisible Man—if not Greek
mythology— it first became a scientific reality in 2006. That year,
researchers at Duke University had created a cloaking device that could make tiny,
two-dimensional objects appear invisible to microwaves.
But this cloak, and others like it, were a far cry
from anything you'd read about in a Harry Potter book or see in a Star Trek
episode (*required references in any article about invisibility cloaks*). One
of the major problems, according to a new paper from Dr. Andrea Alú from the
University of Texas (Austin), is that while it makes objects invisible in one
frequency, it actually makes them more visible under another
frequency. An object made invisible in red light, for example, would be even
more visible in blue light.
But Alú says he has invented a new type of device
that fixes that problem. Like the cloaks of yore, Alú's new design uses
meta-materials (synthetic textiles with properties not found in nature) that
can bend light around an object and make it look like it's not there. But, by
adding an electronic source like a batter to the cloak (making the cloak "active"
as opposed to "passive"), Alú says he can make objects transparent at
"all angles and over all broad bandwidths."
Naturally, a lot of the funding for this research
comes from the Defense Department: Want an airplane or a tank to be invisible
to radar? This is the type of device for you. But it's not just the military
that is interested. Alú says a good chunk of funding comes from wireless
providers. Because if a building is in the way of your wireless signal, making
it invisible might be a better alternative than knocking it down.
Alú says he expects to have a version of this device
built within the next couple of years.
Why the hurry? Maybe it's so we can get one before
Canada does. Researchers at the University of Toronto seem to be neck and neck
with the U.S.
In a recent paper published in the Physical
Review X, Toronto professor George Eleftheriades and his student Michael
Selvanayagam describe a device made up of a series of antennae that can radiate
light and radio waves away from the object it surrounds. But these researchers
have done more than just write about such a device; they've jury-rigged one up using Styrofoam, masking tape, and
12 antennae. It cost under $2,000 and has been nicknamed "the active cloak
machine."
It essentially works like this: Say you shine a beam
of radio waves at an object. When the waves hit the object, they will bounce
back. But if you surround the object with antennae that bounce back the
opposite radio waves, it will seem as if the object is not there.
When asked who might be interested in such a device,
Eleftheriades stuttered a bit.
"The military is the most obvious," he
said. "We have been approached…. I shouldn't say too much about
that."
As for whether this could ever be applied to making
someone or something invisible to the human eye, Eleftheriades says there's no
reason it couldn't scale up, it would just need the right kind of antenna (ones
that don't yet exist).
So, what do researchers have to say about the
age-old question of which would be cooler, flight or invisibility?
"I think becoming invisible," said
Eleftheriades. "Because this experience, no human has had it before. Maybe
we cannot fly on our own, but we know how it feels to fly."
And despite their friendly competition on the
subject, Alú can agree with his colleague on this.
"I would choose invisibility," Alú said.
"Flying is easier to achieve in other ways, and I know exactly how hard it
is to achieve invisibility.
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