Quest for invisibility cloaks revisited by two research groups
By Ross Miller 
posted April 30th 2009 5:26AM
posted April 30th 2009 5:26AM
posted April 30th 2009 5:26AM
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I can't wait to be able to watch porn without running the risk of being caught.
Sorry, had to be said...
Stop watching it on your mom's TV and you won't have to worry about it anymore!
lol, wow, people don't have senses of humour anymore..
They do, and A.C.E.R is an example.
Nor a sense of irony, it seems.
Nor a sense of sarcasm... then again the internet is monotone.
Imagine if these were to fall into the wrong hands: bank & shop robberies would probably become a daily occurrence.
Still, I'm missing the big picture here, which is: COOOOOOOOOOOOOOL!
That assumes that a cloak could evade all forms of detection. But even if you could bend the entire electromagnetic spectrum, which seems unlikely, there are still ultrasonic sensors.
Yes, fortunately it's just a once a year thing at the moment.
As far as I understand it, in these particular designs a range of wavelengths should be cloakable rather than being tuned at one particular wavelength as in the first microwave based devices. But then it does rely on an object being 'cloaked' 'in' a mirror rather than cloaked in empty space. It's conceivable that in time this will be overcome as well. I'm sure it's susceptible at wavelength extremes, but the more extreme the wavelength, the more complicated your detector will have to be. In fact at high frequencies, an observer might have to emit large amounts of dangerous energy in all directions to see a cloaked 'assailant' which is almost certainly totally impractical. At lower frequencies, the light gets increasingly easy to cloak.
I would also remind you that a while back someone figured out mathematics for longitudinal metamaterials that should enable the cloaking of sound. Used in combination and you'll have to turn to fancier methods of detection. With the right materials even MRI might not work. Obviously a scanning electron microscope will, but again, is impractical. Still, the limits to the cloaks efficiency means that, seen as it's unpowered, something will almost certainly be detectable if your sensitivity is high enough. Furthermore, try as they might, the 'cloakee' would have trouble not emitting any light that may be detected, and also have some trouble observing the outside world while limiting the light they emit.
@elmer
Okay, how about pressure sensors in the floor? These could run all the time and, with the appropriate software, only go off when the other sensors *don't*.
Did you see that episode where mythbusters defeated IR security with a bedsheet? Amazing stuff, I bet that would work in countless areas, as the KKK will attest I guess :]
@Wwhat
Actually they defeated the sound alarm with the bedsheet. The IR was beaten with a pane of glass.
I stand corrected, thanks for reminding me the details.
Still amusing how simple 'cloaks of invisibility' really are.
So how long the U.S Army will deploy 20 meter tall robot spiders with lasers and cloaks? followed by infantry in heavy exo-skeletons, armed with pulse lasers ... science fiction... not anymore.
On second thought, 20 meter tall robot spiders don't really need cloaks.
C'mon, the U.S. Army would never deploy 20 meter tall robot spiders. They may deploy 65 foot tall ones, though.
@Nick8708: I see what you did there, but you are wrong. 20 meters is 65.6167979 feet, which is closer to 66 feet than 65.
Hermione always said that a cloak consisting only of isotropic dielectric materials would enable a broadband and low loss invisibility.
Hermione isn't always right.
Shocking, but true.
@superhobo
She has good taste in underwear though.
Yay, now I can make my comments invis-
Meh, this is nothing new.
My cat has been using a cloaking device for years to sneak around.
Let me guess, it is stitched together out of incredibly lame comments like that.
I, for one, would welcome our shimmering reflecting overlords...if ever I could find them.
Its really amazing how sometimes Engadget uses such an intriguing picture with a post, that even if you don't understand whats it about, you're bound to spend some time figuring out whats said in the picture.
The Romulans will be none too happy.
Did anybody notice the measurment scale on that picture? We're cloaking dust. Woo woo......
Soon we'll have the New York Incident, and the California Incident to add to the Philadelphia Incident. Go Cloak!
Engadget did not mention my university, the University of Alberta. We have cloaking material. This is the progress thus far:
The material is designed with a negative light refractive index (man-made) and it based on the cloaks size. The negative light index bends light around the object so you see right through it essentially to the other side.
The problems faced are that it is not dynamic (for size and mobility) and you can't see outside of the cloak (no light enters inside therefore you can't see).
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Women's locker room here I come
You're seriously waiting for a video of an _invisible_ cloak?