Posted on 01/04/2012 1:36:15 PM PST by NormsRevenge
Pentagon-supported physicists on Wednesday said they had devised a "time cloak" that briefly makes an event undetectable.
The laboratory device manipulates the flow of light in such a way that for the merest fraction of a second an event cannot be seen, according to a paper published in the science journal Nature.
It adds to experimental work in creating next-generation camouflage -- a so-called invisibility cloak in which specific colours cannot be perceived by the human eye.
"Our results represent a significant step towards obtaining a complete spatio-temporal cloaking device," says the study, headed by Moti Fridman of Cornell University in New York.
The breakthrough exploits the fact that frequencies of light move at fractionally different speeds.
The so-called temporal cloak starts with a beam of green light that is passed down a fibre-optic cable.
The beam goes through a two-way lens that splits it into two frequencies -- blueish light which travels relatively fast, and reddish light, which is slower.
The tiny difference in speed is then accentuated by placing a transparent obstacle in front of the two beams.
Eventually a time gap opens up between the red and blue beams as they travel through the optical fibre.
The gap is tiny -- just 50 picoseconds, or 50 millionths of a millionth of a second.
But it is just long enough to squeeze in a pulse of laser at a different frequency from the light passing through the system.
The red and blue light are then given the reverse treatment.
(Excerpt) Read more at news.yahoo.com ...
The Pentagon. Pentagon-supported physicists on Wednesday said they had devised a "time cloak" that briefly makes an event undetectable. (AFP Photo/)
Maybe that’s what happened to Obama’s birth certificate
Coincidentally ... I just rented a condo next to a girls boarding school
I seriously doubt this is anything other than a unknown property of photons. A behavior that hasen’t been seen before.
They would have to provide a lot of peer review to show that entropy is being interfered with.
Not to be confused with DARMA from "Lost" .
I don’t even understand the analogy in the article, where a line of cars stops for a train to go by, and the flow of traffic seems normal to the stopped cars and they have no idea a train went by. Huh?
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“Starts with a beam of green light”
I have my new excuse for when the policeman pulls me over.
It’s the old Romulin cloaking device.
Moti? Larry Niven and Jerry Pournelle Ping
It isn't unknown, and it isn't new. Isaac Newton got interested in light after buying a prism at a county fair. Seperation of white light into colors by a prism depends on the same effect: a frequency-dependent speed of propogation of light through some materials. Many devices in wireless technology (example: SAW filters) depend on the same type of phenomenon; light and radio are both EM waves (photons).
I just know that my teenage son and his friends are going to read this and then get caught in the girl’s shower room at school thinking nobody can see them because they’ve got a flashlight with a blue filter in one hand and a flashlight with a red filter in the other hand.
“Ha! Ha! Mr. Johnson! You can’t see us because we’re invisible!”
“Go to the office boys.”
“Another ‘F’ in physics this quarter.”
A Watchmaker gadget!
This cloaking device only works in the Red Light District on Saturday night.
Hmmm, methinks they're a tad beyond the stated test.
This is probably a concept-validation meme for cultural assimilation and generalization.
Seems open use of time and space cloaking and travel is going to be divulged in the near future.
Kind of like how, from an absolute scintific wall against any habitable planets besides Earth, they no "find" a couple a day. What a coinkydink.
Ti’s scary how many Star Trek things are coming to reality!
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