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Scientists Invent World's First Anti-Laser
Velcroman1 writes "Two scientists at Yale University have built the laser's first doppelganger: the anti-laser. While a conventional laser emits a constant beam of light in one direction, the anti-laser simply does the opposite. It takes that same steady light stream and interacts with it in such a way that it absorbs and cancels out the light. And scientists hope the strange creation could help the fight against cancer. A. Douglas Stone, one of the two researchers behind the project, said he came up with the idea for a 'nega-laser' when working with equations for a random laser with his partner in crime, Hui Cao. 'I figured, if we just somehow illuminated the cavity, and replaced the gain medium with something that tends to absorb light, we could essentially reverse the process,' Stone said. Oh, that makes sense."
an anti-laser pointer.
Now it's up to the biologists to create anti-sharks
It shoots a coherent beam of darkness!
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"nega-laser"
I think the prefer vernacular is African-American-laser
...an anti-laser capable of emitting a beam of pure anti-anti-matter.
Now they'll create freaking anti-sharks to attach these to.
Because it sounds like they just figured out how to turn off a laser...
It just sounds like they turned the laser off.
Since this absorbs light rather than reflects it, I think the correct response is or you could just use anything that is opaque (e.g. a brick wall, a thick piece of cardboard, your cat).
I'm shocked. I would've assumed it was priests, or maybe economists.
non sequitur Harry Potter reference
No doubt there's more to it than this. But TFA isn't clear.
Can you install this near the cockpit of planes, making them immune to the dreaded blinding green laser attack? Or for that matter, make something immune to laser guided missiles?
excitingthingstodo.blogspot.com
It sounds just like an inverse tachyon pulse, really.
Lasers have always confused me, and maybe someone smarter than me can explain this. Why can't you just hold up a mirror, or create something even more reflective to make weapons grade lasers useless? Isn't it just light?
I call them "walls"
I think it's more complicated than that. You'd definitely need at least a tachyon burst.
That's "Darkness Amplification by Stimulated Absorbance of Radiation"
Scientist: We have an amazing toy! It does weird stuff, but nothing useful. In fact it's so weird, we don't even know what's happening. Who knows, once we figure it out, we might find that it is similar to radiation therapy used today to combat cancer.
Reporter: The scientists believe that someday it could be used in our fight against cancer
Editor: hmm... it's not really that big of a story. The only thing that makes it interesting enough to print is the bit about cancer.
Final printed version: It CURES cancer!
Free unix account: freeshell.org
Two scientists at Yale University have built the laser's first doppelganger: the anti-laser.
I do not think this word means what you think it means.
I invented an anti-laser too. I call it a mirror. And it has 101 other uses!
If we could put one of those on an airplane and rig up a system that could target people lasering aircraft, pilots wouldn't have to worry about being "lased" while they're on final approach. It's a serious problem and as a private pilot I have no sympathy for people who lase aircraft, especially during final approach when you're going "low and slow" or when you're doing your base/final approach.
Now we have to invent anti-sharks!
I thought a doppelganger was a "Twin" or as Dictionary.com says "–noun a ghostly double or counterpart of a living person." Wouldn't this be more like the antithesis of a laser? Just throwing that out there.
An anti-laser would emit light in every direction except for a tightly focused beam.
translate as "We're looking for funding.".
I can't speak for brick walls or pieces of cardboard, but cats tend to catch fire when lasers are shined on them.
I hope a diamond-encrusted gold bust of my magnificently pale ass will help to fight cancer.
A bust of your ass?
bust
n.
1. A sculpture representing a person's head, shoulders, and upper chest.
What does your face look like?
Do you have someone busting your ass right now?
1) Anti-laser
2) ?
3) Profit!
If you could reason with religious people, there would be no religious people
If you shine a laser on a matte-black painted surface, can you see the dot where the light hits? If so, then it's not absorbing all the light - just a portion of it.
BBC article on the same subject talks only about using in optical computers.
http://www.bbc.co.uk/news/technology-12453893
I want a device that I can point to a screen and make the slides disappear
Why are we getting ours news from Fox? For every concrete nit-picky criticism I can make about the article (improper use of the word "doppelganger", the strangely "compressed" quotation at the end) there are some serious conceptual issues with the article as well. I'm not convinced the author understands half of what's going on. I've gotten the distant impression from the interviews that this is a device that takes in a laser light and dissipates the light into heat, but the article seems to be implying any number of things from an EMP-like device that cancels out lasers to a laser shield. There was no adequate explanation of how the device could be used for cancer treatment. Finally, and the one thing that gives the article that special Fox News touch, is the subtle but definitely present underlying tone of "This technology will be the death of us all, because science is really complicated, I don't understand it, and I don't like things I don't understand."
I sometimes ask revealing, often ignorant-seeming questions. Maybe they're harder to answer than you think.
I saw this in Nature when it first was published. It's completely useless. Basically what they are suggesting is putting weak absorber inside a high-Q cavity. The result? High absorption at the fabrey-perot modes. Surprise, surprise.
Guess what - absorbing light isn't particularly difficult. This is probably the most overblown waste of memory I have every read.
this could be an important safety measure to prevent crossing of streams...
... just heaved a huge sigh of relief.
Depends on the power of the laser. Besides, they've still blocked the laser for at least some period of time.
"According to Stone and other physicists, the creation of the anti-laser -- the eggheads refer to it as a coherent perfect absorber (CPA) -- has been one of the defining technological innovations of the past century. So could this anti-laser have just as much impact on society’s future?"
Considering the source, that eggheads comment comes off as pejorative. Cool editorializing bro.
Ah, so I'm NOT the only one who noticed that this article linked to a Fox News story.
Anti-news, indeed. Or, to use the terminology from this story, "nega-news".
You are welcome on my lawn.
This is just constructive or destructive interference of two beams of light, no different than a resonant-cavity photodiode, which has existed for 20 years. Lasing, if you recall, is stimulated emission, represented by one of Einstein's coefficients. The opposite physical process, which is the opposite Einstein coefficient, is absorption, which is always stimulated (there's no such thing as spontaneous absorption). We've long known about "anti-lasing"--it's called absorption.
Nothing to see here, move along.
So that just means you need more cats.
Seven puppies were harmed during the making of this post.
I'm TOTALLY going to $&*# with the cat's head!
Actually, the OP is correct. the matte black paint does absorb all of the light. If you look at the other side of what ever it is painted on, you no longer see the laser light. It doesn't even have to be matte black paint. It can be any color paint you want.
Proof of concept: Take a piece of poster board and paint it whatever opaque color you want. Place a light meter on the unpainted side. Shine a laser on the painted side and record the change in light as detected by the meter. If there isn't any, then the painted poster board absorbed all of the laser light.
When I used to do black and white photography, I used to use nega-light all the time when loading film into cartridges. The difference was that instead of black poster board, I used a black cloth sack. It effectively absorbed all of the visible light that hit it. It was much more impressive than only being able to absorb one specific wavelength of light at a time.
and emits it in the other direction.
You will be assimilated.
Can this technology be adapted as a defense used by a cyborg alien race, by any chance?
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To create a laser, you need to excite the atoms in the medium. So with an anti-laser, does that mean the atoms are depressed? Maybe they need a little atomic prozaic.
Holy shit, did he just invert the polarity?
The world you experience is only a close approximation of reality.
Why are we getting ours news from Fox?
Fox News reported something the mainstream media didn't.
/. and lots of other technews sites. Statistics is also science, so don't generalize.
You anti-Foxers have this infinite loop problem:
1) Fox News reports something no other source does;
2) Libs yell "LA LA LA I CAN'T HEAR YOU FOX IS BIASED!" and remain ignorant of the story;
3) Rinse and repeat.
I can name numerous stories the MSM ignores, and only Fox reports, but you wouldn't want to hear about it because Fox reported it!
And your whole anti-science thing by Fox viewers is just BS generalization. Sure, there are some creationists out there who would naturally gravitate there. But I am intellectually curious enough to read
Slashdot "libertarians": Small government for me, big government for those I disagree with. -1, I disagree with you
If these guys have come up with something that will scale up to megawatt powers, this could spell the end of overhead power lines. It could power anything line-of-sight, including satellites. It could also transmit solar power harvested from space to the earth. Laser light can be focused tightly onto a target, unlike microwaves or radio-based radiation. This could be very efficient...
Reflection is not absorption. A piece of high-gloss tin-foil doesn't let any light through either, but absorbs very little. A material that completely absorbed all the light hitting it would always look completely black - you wouldn't be able to discern any texture. This anti-laser would be able to admit a laser, without letting any light back out.
came up with the idea for a "nega-laser" when working with equations for a random laser with his partner in crime
Wow, some people are really taking their DC Universe Online character builds seriously. Can I join their guild?
You are not a brain: http://books.google.com/books?id=2oV61CeDx-YC
most technologies build on prior discovery; Years ago a non-coherent version was descrbed in JIR
http://www.artofhacking.com/IET/NEWTECH/live/aoh_darkbulb.htm
Everyone knows that to make an anti-laser, you just have to switch the polarity!
We now have flash-darks for when it's light?
Scientist: Fuck you! Reporter: Scientist rapes journalist. (from SMBC)
Sooo... lightsaber anyone?
Oh, wait.
You mean its a real Dark Sucker?
I've heard about that in a campfire skit. Isn't that why burnt stuff turns black, because the light gets out?
*DO* look at the anti-laser with the damaged eye???
I am an ACCA student. Got a query on Accountancy/Finance? Maybe I can help!
I wonder what implications this discovery will have in holographic technology. Could there be such thing as an anti-hologram?
Since the provided Fox News link is useless, here is the link to the original Science paper published today by the researchers. Requires paid access, if you don't have that, try PhysicsWorld.
Basically, it is a time-reversed laser, so it absorbs coherent light.
What a great item to put in the pool of my BOFH responses ;-) Thanks.
We will finally know the Speed of Dark!
That was my first thought too :P
The article didn't mention a thing about curing cancer. It even specifically stated it could help in the treatment of it. Reading ftw.