2% The Two Percent Company
[ - ]
| Large Type Edition |
[ - ]
[ - ]
| Navigate the Rants




Categories

Special Collections
|
[ - ]
[ - ]
|
Subscribe to the
2%Co Rants:



Syndicate this site:
ATOM
RSS 1.0
RSS 2.0
|
[ - ]
[ - ]
| The Usual Suspects
On Hiatus
Carnivals
Carnival of the Godless
Skeptics' Circle
Tangled Bank

Gone But Not Forgotten
Lost to the Mists of Time
|
[ - ]
[ - ]
| Archives (Weekly)
% 2016.11.06 » 2016.11.12
% 2009.04.05 » 2009.04.11
% 2009.03.15 » 2009.03.21
% 2009.03.08 » 2009.03.14
% 2009.03.01 » 2009.03.07
% 2009.02.15 » 2009.02.21
% 2009.01.25 » 2009.01.31
% 2009.01.18 » 2009.01.24
% 2009.01.04 » 2009.01.10
% 2008.12.21 » 2008.12.27
% 2008.11.16 » 2008.11.22
% 2008.11.09 » 2008.11.15


Archives (Monthly)
% 2016 November
% 2009 April
% 2009 March
% 2009 February
% 2009 January
% 2008 December
% 2008 November
% 2008 October
% 2008 September
% 2008 July
% 2008 June
% 2008 April
% 2008 January
% 2007 November
% 2007 October
% 2007 August
% 2007 July
% 2007 June
% 2007 May
% 2007 April
% 2007 March
% 2007 February
% 2007 January
% 2006 December
% 2006 November
% 2006 October
% 2006 September
% 2006 August
% 2006 July
% 2006 June
% 2006 May
% 2006 April
% 2006 March
% 2006 February
% 2006 January
% 2005 December
% 2005 November
% 2005 October
% 2005 September
% 2005 August
% 2005 July
% 2005 June
% 2005 May
% 2005 April
% 2005 March
% 2005 February
% 2005 January
% 2004 December
|
[ - ]
[ - ]
|
« Bad Decision Maker? No Problem! The RantsTruer Words Ne'er Spoken »

Invisibility and Reverse Light
2006.05.26 (Fri) 11:11

We freely admit it: we totally geek out when science fiction concepts crawl closer and closer to becoming reality. As reported by both Reuters and MSNBC, scientists think they may actually be able to engineer that old standby of traditional fantasy: the invisibility cloak!

From Reuters:

Two separate teams of researchers have come up with theories on ways to use experimental "metamaterials" to cloak an object and hide it from visible light, infrared light, microwaves and perhaps even sonar probes.

...

The concept begins with refraction — a quality of light in which the electromagnetic waves take the quickest, but not necessarily the shortest, route. This accounts for the illusion that a pencil immersed in a glass of water appears broken, for instance.

"Imagine a situation where a medium guides light around a hole in it," Physicist Ulf Leonhardt of Britain's University of St. Andrews, wrote in one of the reports, published in Friday's issue of the journal Science.

The light rays end up behind the object as if they had traveled in a straight line.

"Any object placed in the hole would be hidden from sight. The medium would create the ultimate optical illusion: invisibility,["] Leonhardt wrote.

Currently, "cloaking devices" like those used on stealth craft operate by misdirecting reflected electromagnetic waves — like radar — which renders them "invisible" to certain sensors.

This technology is a far different story. Rather than odd reflections, it relies on refraction, and sends any photons along on their way as if there was nothing stopping them in the first place.

On MSNBC:

The most exotic technologies involve "metamaterials," blends of polymers and tiny coils or wires that twist the paths of electromagnetic radiation.

"There are recipes for controlling metamaterials," explained University of Pennsylvania electrical engineer Nader Engheta, who published his own invisibility recipe last year. "Metamaterials are very interesting products."

But MSNBC also points out some salient factors regarding the manufacture of invisibility gear:

  • For a total invisibility effect, the waves passing closest to the cloaked object would have to be bent in such a way that they would appear to exceed relativity's light speed limit. Fortunately, there's a loophole in Albert Einstein's rules of the road that allows smooth pulses of light to undergo just such a phase shift.
  • The invisibility effect would work only for a specific range of wavelengths. "There is a price to be paid if you want a thin cloak, in that it operates only over a narrow range of frequencies," Pendry said.
  • The cloak could be made to cover a volume of any shape, but "you can't flap your cloak," Pendry said. Moving the material around would spoil the effect.
  • The tiny structures embedded in the metamaterial would have to be smaller than the wavelength of the electromagnetic rays you wanted to bend. That's a tall order for optical invisibility, because the structures would have to be on the scale of nanometers, or billionths of a meter. It's far easier to create radar invisibility, Pendry said: "You're talking millimeters" — that is, thousandths of a meter.

And Reuters mentions that:

Anyone making such a cloak would have to choose what form of radiation one wanted invisibility from, Shurig [sic] said. The invisibility would work both ways — a person hidden from the visible light spectrum would have to use infrared or sonar or microwaves to see out, he said.

Even with these drawbacks, though, the potential inventions and uses are truly, truly keen. Even in mundane spheres, some great ideas have been put forth — for instance, cloaking large structures in radiowave-specific invisibility cloaks to enable cell phone signals to get through to frequently "dropped" areas, or carefully shielding sensitive medical equipment from just the right "bad" electromagnetic waves while still allowing them to function in the wavelengths they require. The MSNBC article has numerous links, including one to the Pendry, et al paper published on the subject.

And, speaking of doing neat tricks with light, this news comes on the tail of an absolutely fantastic breakthrough earlier this month, when Robert Boyd of the University of Rochester managed to make light travel so fast it went backwards:

As if to defy common sense, the backward-moving pulse of light travels faster than light.

...

[says Robert Boyd,] "Theory predicted that we could send light backwards, but nobody knew if the theory would hold up or even if it could be observed in laboratory conditions."

Boyd recently showed how he can slow down a pulse of light to slower than an airplane, or speed it up faster than its breakneck pace, using exotic techniques and materials. But he's now taken what was once just a mathematical oddity — negative speed — and shown it working in the real world.

"It's weird stuff," says Boyd. "We sent a pulse through an optical fiber, and before its peak even entered the fiber, it was exiting the other end. Through experiments we were able to see that the pulse inside the fiber was actually moving backward, linking the input and output pulses."


[our emphasis]

Holy...shit. This stuff is so mind-numbingly amazing we're clapping our hands at the sheer genius and absurdity of it. Check out the University of Rochester article for some good analogies, great explanations, and super graphics illustrating the process. Our minds are racing with interesting concepts — both real and fictional — that could develop from this fascinating observation.

Thanks go out to BJS for the Rochester link (via Jake, who had a smart entry in the latest Skeptics' Circle).


— • —
[  Filed under: % Science & Technology  ]

TrackBack URL for this entry: http://www.twopercentco.com/rants/tpc-trkbk.cgi/331

Comments (2)

BigHeathenMike, 2006.05.26 (Fri) 21:48 [Link] »

Science rocks harder than if KISS and Metallica had babies and they formed a band that had sex with a piece of granite. That's some hard rockin'.



Charlene Dewbre, 2007.10.11 (Thu) 11:46 [Link] »

This is the coolest stuff, ever. Studies on light manipulation - hell, the minutiae of the universe, period, blow me away.

What's always fascinating: where matter acts as two substances simultaneously. Light's the star of that show, acting as particle and wave.

It's very like when a teacher in high school told us that glass is a liquid. Now, we know that glass isn't a liquid, but an amorphous solid - still it's very cool that glass has the properties of both a liquid and a solid.

I wonder when I can buy my very own light deflector shield? How Star Trek!




— • —


— • —

Enter your comment below

Name —
E-mail —
URL —
Remember me?
Subscribe to this Rant? (We'll notify you of new comments.)

Comments —
(Allowed HTML: a href, b, i, br, ol, ul, li, blockquote)



Please Post only once; if you do not see your comment immediately, Refresh the Rant page.
Your comment will autopreview above, if you have Javascript enabled.

Read the Two Percent Company's Comment Policy before diving into the deep end.


To subscribe to this Rant without commenting, fill in your e-mail address below:




|
[ - ]


Terms of Use — • — Privacy Policy — • — FAQ
[ - ]
| Protecting our Civil Liberties
ACLU
EFF: Support Bloggers' Rights!
Individual-i

Bullshit Busters
JREFSkeptic's Dictionary
QuackwatchSnopes.com
SymantecMcAfee
SophosSnopes.com

|
[ - ]
[ - ]
|
|
[ - ]
[ - ]
|
Buy 2%Co Products
2%Co Stores


Visit the 2%Co Wish List
|
[ - ]
[ - ]
|
Amazon.com


Recommended by us:


Recommended to us:

|
[ - ]
[ - ]
|
|
[ - ]
[ - ]
| Where can you find 2%Co?

Site MeterGlobe of Blogs
Atheism OnlineThe Truth Laid Bear
BlogwiseBlogarama
BlogsharesTechnorati

2%Co Search Rankings

Link to our Rants
2%Co Rants


Link to our Allison DuBois: Debunked! collection
Allison DuBois: Debunked! (2%Co)


The 2%Co Rants powered by
MovableType
|
[ - ]