Fri Feb 06, 2009 9:43 am
JenDiMarco wrote:
I was reading the March issue of Popular Science about metamaterial. The photo shown was of a person in a poncho-type jacket... and they looked almost entirely invisible (see through).
This link:
tinyurl.com/yg7hrx3 is the results for metamaterial at the magazine's website. I was amazed. And it's already so advanced that by Prime Time we should have something truly incredible to draw on.
Though... I did have to wonder this:
If metamaterial can do this... is Vanish still so great?
They were already talking about metamaterial back in 2008, by the way (see below) but the March issue showed an actual piece of clothing which they only proposed in 2008. It is now a reality.
WHAT: A way to make objects invisible. The trick is to use metamaterial, a complex hybrid structure of metal and insulator that makes light move around an object like air flowing over an airplane wing. In a process called refraction, these materials interact with light in such a way that it travels faster through the metamaterial than it does through a vacuum, the famed c in Einstein´s special theory of relativity. Properly tuned, the light emerges from the shield as if there were no object present. But unfortunately for would-be spies, it´s very difficult to make cloaking devices that work on more than one wavelength of light at a time.
WHY: Military stealth. A B-2 bomber isn´t truly invisible to radar. It just absorbs and redirects the radar waves, making the plane much harder to spot (its radar signature is the size of a pigeon rather than an aircraft). A bomber, tank or building covered in a radar-sensitive metamaterial shield would literally disappear from radar screens.
WHEN: For certain applications, commercial deploy-
ment could be within a decade. The best-studied metamaterials work only on microwaves. Duke University physicist David R. Smith hopes to shield a toaster-size object from microwave frequencies within the next six months. Metamaterials that work on visible light-which isn´t a single frequency
but a spectrum of frequencies-are at a more primi-
tive state. A specific meta-
material design would be required to redirect each
frequency in the visible range, and integrating that many components into a device might take 10 years for the initial lab demonstration alone.
WHO: The mathematical models were developed independently by two groups, the first led by Ulf Leonhardt at the University of St. Andrews in Scotland and the second by Smith with John Pendry of Impe-
rial College London. Smith could soon prove the concept experimentally.
FAQs
Has anyone made a metamaterial?
Yes. Scientists in the U.S. and the U.K. have made metamaterials with what´s called a
negative index of refraction. Generally, these metamaterials are coiled metal wires surrounded by air or another insulator and affect only microwave radiation.
Can the cloaking be perfect?
Almost. Any metamaterial absorbs a little bit of light and therefore casts a slight shadow.
Could an actual cloak ever hide a person?
Yes, but current designs would work only if you painted yourself all one color. A cloak, which for comfort´s sake needs to be pretty thin, could bend radiation of just a single frequency, so it could only hide an object of one color. There´s a possibility, though, that a thick shell could include a wider
variety of metamaterials and broaden the invisibility to
multiple frequencies.
What would the inside of the cloak look like?
If a cloak worked over the entire spectrum, the lack of light would make the inside black, and you wouldn´t be able to see outside. No one knows exactly what would happen if you turned on a flashlight inside the cloak.
Fri Feb 06, 2009 10:06 am
JenDiMarco wrote:
The cloak here isn't skin tight because that would be kind of indecent. But imagine how smooth it would be if it were?
« Reply #12 on 9.20.2009 at 4:51pm »
Sun Feb 08, 2009 8:49 am
JenDiMarco wrote:
Of course, as with all SF, any writings about the "future" really, you run the risk of being short-sighted. Of not thinking fantastic enough. Vanish seems like an amazing skill until you see something like metamaterial.
I don't think we should completely freak out however. I think some gentle tweaks to the universe will help the Immortal skills stand up to whatever technology may throw at us.
For instance, this evening Launa and I considered simply making Immortals completely unreadable when Vanished (other Immortals can't even tell there's another Immortal around) and also lengthening the time for which they can stay Vanished. This, to me, seems to balance out the effects that metamaterial brings to the table.
We also considered making moment of a Vanished Immortal faster. As though they were almost warping a short ways.
EJ, you can weigh in on these ideas or propose some of your own -- anyone can propose other ideas, actually! I simply want to make sure that the Immortal skills stay amazing.
Jennifer
Thu Feb 12, 2009 12:57 am
JenDiMarco wrote:
Another example of more tactical use of metamaterial:
