• Forum Moderator applications are now open! If you're interested in joining an active team of moderators for one of the biggest Pokémon forums on the internet, click here for info.

Pentagon-backed 'time cloak' stops the clock

G

GrnMarvl14

Lying
Joined
Jan 4, 2003
Messages
13,846
Reaction score
4
Source.

Pentagon-supported physicists on Wednesday said they had devised a "time cloak" that briefly makes an event undetectable.

It's one thing to make an object invisible, like Harry Potter's mythical cloak. But scientists have made an entire event impossible to see. They have invented a time masker.

Think of it as an art heist that takes place before your eyes and surveillance cameras. You don't see the thief strolling into the museum, taking the painting down or walking away, but he did. It's not just that the thief is invisible - his whole activity is.

What scientists at Cornell University did was on a much smaller scale, both in terms of events and time. It happened so quickly that it's not even a blink of an eye. Their time cloak lasts an incredibly tiny fraction of a fraction of a second. They hid an event for 40 picoseconds (trillionths of a second), according to a study appearing in Thursday's edition of the journal Nature.

We see events happening as light from them reaches our eyes. Usually it's a continuous flow of light. In the new research, however, scientists were able to interrupt that flow for just an instant.

Other newly created invisibility cloaks fashioned by scientists move the light beams away in the traditional three dimensions. The Cornell team alters not where the light flows but how fast it moves, changing in the dimension of time, not space.

They tinkered with the speed of beams of light in a way that would make it appear to surveillance cameras or laser security beams that an event, such as an art heist, isn't happening.

Another way to think of it is as if scientists edited or erased a split second of history. It's as if you are watching a movie with a scene inserted that you don't see or notice. It's there in the movie, but it's not something you saw, said study co-author Moti Fridman, a physics researcher at Cornell.

The scientists created a lens of not just light, but time. Their method splits light, speeding up one part of light and slowing down another. It creates a gap and that gap is where an event is masked.

"You kind of create a hole in time where an event takes place," said study co-author Alexander Gaeta, director of Cornell's School of Applied and Engineering Physics. "You just don't know that anything ever happened."

This is all happening in beams of light that move too fast for the human eye to see. Using fiber optics, the hole in time is created as light moves along inside a fiber much thinner than a human hair. The scientists shoot the beam of light out, and then with other beams, they create a time lens that splits the light into two different speed beams that create the effect of invisibility by being too fast or too slow. The whole work is a mess of fibers on a long table and almost looks like a pile of spaghetti, Fridman said.

It is the first time that scientists have been able to mask an event in time, a concept only first theorized by Martin McCall, a professor of theoretical optics at Imperial College in London. Gaeta, Fridman and others at Cornell, who had already been working on time lenses, decided to see if they could do what McCall envisioned.

It only took a few months, a blink of an eye in scientific research time.

"It is significant because it opens up a whole new realm to ideas involving invisibility," McCall said.

Researchers at Duke University and in Germany's Karlsruhe Institute of Technology have made progress on making an object appear invisible spatially. The earlier invisibility cloak work bent light around an object in three dimensions.

Between those two approaches, the idea of invisibility will work its way into useful technology, predicts McCall, who wasn't part of either team.

The science is legitimate, but it's still only a fraction of a second, added City College of New York physicist Michio Kaku, who specializes in the physics of science fiction.

"That's not enough time to wander around Hogwarts," Kaku wrote in an email. "The next step therefore will be to increase this time interval, perhaps to a millionth of a second. So we see that there's a long way to go before we have true invisibility as seen in science fiction."

Gaeta said he thinks he can get make the cloak last a millionth of a second or maybe even a thousandth of a second. But McCall said the mathematics dictate that it would take too big a machine - about 18,600 miles long - to make the cloak last a full second.

"You have to start somewhere and this is a proof of concept," Gaeta said.

Still, there are practical applications, Gaeta and Fridman said. This is a way of adding a packet of information to high-speed data unseen without interrupting the flow of information. But that may not be a good thing if used for computer viruses, Fridman conceded.

There may be good uses of this technology, Gaeta said, but "for some reason people are more interested in the more illicit applications."

Fridman's work was part-supported by the Defense Advanced Research Project Agency, or DARPA, a Pentagon unit which develops futuristic technology that can have a military use. Its achievements include DARPANet, a predecessor of the Internet.
Click to expand...

Very cool invention, though I'm trying to think up what military applications beyond assassination this would be used for (assuming this can move beyond merely proof of concept). And legitimate mainstream applications, as well, beyond a simple novelty (what super-obvious application is eluding me?).
 
This is very interesting. This new device in itself means very little, but the potential for it is huge.
 
A true cloaking device. Too bad by the time it actually becomes practical, we probably won't have a need for the technology :/
 
SmearglePaints said:
This is stupid. Basically, they closed their eyes. How do you "hide" and "event"?
Click to expand...

Because they interrupted the flow of light to surrounding people's eyes. That's how we see stuff, so if they stopped that input for however long, the scene we're looking at wouldn't look different, but it would be different (a piece of paper stolen, etc.) by the time the device times out and the observer starts getting the usual amount of sensory input again. It's all a matter of light and interrupting its flow to the observer's eyes, none of that "time-stopping" or "temporary pausing" or all of that time-based hocus-pocus.
 
I tried to cover the existence of me making this post, but as it can only cover 40 picoseconds and this post took longer than that to post, it still went through.
 
Jack Tschitt said:
Because they interrupted the flow of light to surrounding people's eyes. That's how we see stuff, so if they stopped that input for however long, the scene we're looking at wouldn't look different, but it would be different (a piece of paper stolen, etc.) by the time the device times out and the observer starts getting the usual amount of sensory input again. It's all a matter of light and interrupting its flow to the observer's eyes, none of that "time-stopping" or "temporary pausing" or all of that time-based hocus-pocus.
Click to expand...
So, they closed their eyes. Right.
 
Stopping the clock is amazing technology? I should sell them my xbox 360 then, the time on it is broken and has been stuck at 7:26 AM for 4 years.
 
SmearglePaints said:
So, they closed their eyes. Right.
Click to expand...

The point is: the final product, if technology ever makes it possible, will cause everyone to close their eyes to an event happening, thus making it appear as if it never happened or make the effects of the event unexplainable.
 
SmearglePaints said:
So, they closed their eyes. Right.
Click to expand...

Figuratively, yes.

Tsuness said:
The point is: the final product, if technology ever makes it possible, will cause everyone to close their eyes to an event happening, thus making it appear as if it never happened or make the effects of the event unexplainable.
Click to expand...

The latter would be correct. The observer would see what happened as soon as the device timed out. But the wouldn't see the event actually transpiring.
 
It took me a few reads of the article before I felt I really had a sense of what exactly this is. Very cool stuff though. I still don't fully understand why they say they are manipulating time, from what I understand they are just manipulating the speed of light by changing its wavelength and putting it through a different medium. I don't see how that equates to manipulating the time dimension, unless I'm just not fully understanding this.

GrnMarvl14 said:
Very cool invention, though I'm trying to think up what military applications beyond assassination this would be used for (assuming this can move beyond merely proof of concept). And legitimate mainstream applications, as well, beyond a simple novelty (what super-obvious application is eluding me?).
Click to expand...

Possibly uncrackable data encryption? Faster processors using the multitasking ability that they talked about in the article? These are not necessarily military specific, but encryption would be very useful to them. I'm not an expert in the field, so these are just random ideas.
 
SmearglePaints said:
So, they closed their eyes. Right.
Click to expand...

You realize that's exactly what they didn't do, or so it seems to me. The way I interpreted it, the observer is still observing the same thing as before the event takes place, yet because of the light delay, the action has taken place before it's noted. None of that involves what you would call closing your eyes. Might be wrong though

TheMysteryno. said:
Possibly uncrackable data encryption? Faster processors using the multitasking ability that they talked about in the article? These are not necessarily military specific, but encryption would be very useful to them. I'm not an expert in the field, so these are just random ideas.
Click to expand...

I would say encryption as well, but for the most part just military applications (as well as cyberwarfare perhaps, computer viruses). I don't really know.
 
I wouldn't care if the CIA made a time machine. Money is being wasted to create science that makes it easier for people to kill and deceive other people. Technology advances, humanity recedes, as usual.
 
Please note: The thread is from 15 years ago.
Please take the age of this thread into consideration in writing your reply. Depending on what exactly you wanted to say, you may want to consider if it would be better to post a new thread instead.
Back
Top Bottom