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"Cone of Silence" Possible Say Scientists

Posted by ScuttleMonkey on Sat Jan 12, 2008 07:20 AM
from the is-leonard-bernstein-licensed-to-kill dept.
Science Technology
Ponca City, We Love You writes "The 'Cone of Silence,' once a staple of 1960's television shows, is now possible say scientists at Duke University who first demonstrated a working 'cloak of invisibility' that works at microwave frequencies in 2006. Such a cloak designed for audio frequencies might hide submarines in the ocean from detection by sonar or improve the acoustics of a concert hall by effectively flattening a structural beam. Although the theory used to design such acoustic devices so far isn't as general as the one used to devise the microwave cloak, the finding nonetheless paves the way for other acoustic devices. 'We've now shown that both 2-D and 3-D acoustic cloaks theoretically do exist,' says Researcher Steven Cummer. 'It opens up the door to make the physical shape of an object different from its acoustic shape.'"
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Related Stories

[+] Cloak of Invisibility Coming Soon 296 comments
davaguco writes "It seems that we will finally be able to make ourselves invisible" It seems like this story resurfaces every few months and then gets submitted a zillion times so here it is. Personally I'm still waiting for my cloak of evasion. 20% miss chance is awesome.
Submission: "Cone of Silence" Possible say Scientists by pickens (49171)
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  • Sadly the article is sorta light on details.

    Anyone have some insight on how exactly this sort of thing is accomplished, aside from the article's reliance on materials that seemingly don't exist yet?

    • Re:Light on details... (Score:5, Informative)

      by thelamecamel (561865) on Saturday January 12 2008, @08:55AM (#22013832)
      It seems they're importing ideas from photonics and metamaterials - light and sound, they're all waves. What's been done with light (in Britain and Germany IIRC) is some object has been surrounded by a 'cloaking device', and for one specific wavelength of light, the cloaking device and object become completely transparent and invisible. Light flows through the cloaking device and around the object that's being hidden (well that's the hand-wavy explanation). To do funky stuff like cloaking, you need (in optics) a material with negative refractive index (so light seems to travel backwards). People get this by arranging tiny (smaller than the wavelength of light involved) resonators in a regular pattern. The light wave "doesn't see" the individual resonators, but instead "sees" an overall medium. However, this medium can have quite abnormal properties (such as negative refractive index). Another way of looking at the device is that you surround the object with resonators that specifically cancel out any effect on the sound/light wave that the object makes. So you get no net effect on the wave, so it's as if the object wasn't there. Presumably the people at Duke have transplanted some designs for light and have worked through the corresponding acoustic wave equations to find "negative refractive index sound" (though i'm not sure what their resonators would look like, because light is more complicated than sound and most light metamaterial designs use properties of both E and H components of light. Maybe they can cheat because sound travels faster in, say, wood than air)
    • The details on how they do it are in the audio portion of the article. What? You didn't hear the audio? What?

    • Would ya believe.....

      Two plastic cups strapped over your ears?

      If you don't get the reference [wouldyoubelieve.com], you're too damned young.

  • Max vs. the Chief (Score:5, Funny)

    by pipingguy (566974) * on Saturday January 12 2008, @07:35AM (#22013372) Homepage
    Max: What?
    Chief: What?
    Max: What?
    Chief: What?

    I've always wanted to build one of those, I even have a sketch, bill of materials, etc.

    • I even have a sketch, bill of materials, etc.
      I find that hard to believe

      Would you believe a set of notes and a written shopping list?
      Not really

      How about a picture drawn with crayons?
      • Tee-hee! You know those old womens' hairdryer things? Take two of those and bingo! Well, sort of.

        I've got 200 bucks to start creating one.
        • And, no, I'm not kidding. email me if you can find me and we'll start planning.

          This wouldn't be the first time I've created something for no reason at all due to internet inspiration.

          It'd be the dumbest thing I've ever attempted, but what the hell...

      • Anyone? Was there even a single other show that used the Cone of Silence?
        Not to my knowledge and I watched Get Smart when it was new.

        "Oh come on, Max! You know that thing never works."

  • The invisible cone (Score:4, Funny)

    by Anonymous Coward on Saturday January 12 2008, @08:17AM (#22013618)
    Here is an image to explain it all:
    http://icanhascheezburger.com/2008/01/12/funny-pictures-invisible-ice-cream-cone/ [icanhascheezburger.com]

    • Re:The invisible cone (Score:4, Funny)

      by myth_of_sisyphus (818378) on Sunday January 13 2008, @12:09AM (#22021886)
      That reminds me of trying to explain "I can has cheezburger" to my hairstylist.

      While cutting my hair one day, she mentioned she loved taking pictures of her cats.

      I said "You should check out this new craze. It's called "I can has cheezburger" and you take a picture of a cat doing something, and then you put a caption on it that is clever, then you post it on the internet."

      She says "I already go to a site and upload my cat pictures."

      I say "Well, it's not really cat pictures. It kind of 'transcends' cat pictures and becomes something else. Kind of a "meta-cat picture".

      She says "....uhhhh...what?..."

      I say "I can't really explain it, you kind of have to see it. Go to this website: 'I...can...has...cheezburger... spelled with a z and no 'e'"

      She says "....uhhhh...what?...."

      I say "I'll write it down...the site is named after the first cat picture called "I can has cheezburger". Now that cheezburger cat is famous in his own right. He's called 'Happycat'."

      She says "the pictures are of cats eating cheeseburgers?"

      I say "No, just captioned cheezburger."

      She says "Ok"

      She now thinks I'm completely insane and is silent for the rest of the haircut.

  • When is acoustic shape same as physical anyway? (Score:4, Insightful)

    by noidentity (188756) on Saturday January 12 2008, @08:18AM (#22013626)

    'It opens up the door to make the physical shape of an object different from its acoustic shape.'

    Since when has an object's acoustic shape ever matched its physical shape to begin with? It's usually more like a sphere.

  • "Cone of Nonsense" Possible Says Teckla (Score:5, Funny)

    by Teckla (630646) on Saturday January 12 2008, @08:19AM (#22013630)

    Researchers at the Teckla Institute for Scientific Advancement have determined that it's possible to have a "Cone of Nonsense" that remains stable for months, even years.

    "Take, for example, the Cone of Nonsense generated at Slashdot, an online site dedicated to News for Nerds," says Dr. Teckla, a long-time scientist at the Institute. "We've identified at least two powerful Cone of Nonsense forces there, which we've named the 'Roland Piquepaille Effect' and the 'Ponca City, We Love You Force'."

    Combine these potent forces with 'ScuttleMonkey Energy', and the result is a stable, if frightening, Cone of Nonsense.

    "We're not sure what happens if you enter this Cone of Nonsense," commented Dr. Teckla, "But we're pretty sure it drops your I.Q. by 50 points.

    • What about the GNAA? Are they in their own cone of nonsense or do they coexist with Slashdot in its cone?

  • bad news for bats (Score:5, Funny)

    by Anonymous Coward on Saturday January 12 2008, @08:30AM (#22013692)
    "It opens up the door to make the physical shape of an object different from its acoustic shape."

  • A staple of 60s television shows? (Score:3, Interesting)

    by Chess_the_cat (653159) on Saturday January 12 2008, @08:33AM (#22013708) Homepage
    The only show I can think of that featured the Cone of Silence was Get Smart! What other shows featured this technology?

  • Already using one (Score:5, Funny)

    by Whiteox (919863) <htcstech AT gmail DOT com> on Saturday January 12 2008, @08:41AM (#22013758) Journal
    Every time my wife asks me to do something, I don't hear it.
    Every time I ask her to do something, she doesn't hear me.

  • Can't find better references (Score:5, Informative)

    by MonkeyBoyo (630427) on Saturday January 12 2008, @08:52AM (#22013806)
    Here is the old theoretical paperOne path to acoustic cloaking, New Journal of Physics, v. 9, 45, 2007. [pdf reprint] [duke.edu] The Science Daily article is just a reprint of the Duke press release. [duke.edu]Steven A. Cummer [duke.edu] seems to provide PDF "reprints" [duke.edu] of all his papers but the new one isn't in that list. Nor can it be found on David Smith' page [duke.edu], David Schurig's old Duke page [duke.edu], or his new NC State page [ncsu.edu], Sir John Pendry's page [ic.ac.uk], or Anthony Starr's page [sensormetrix.com].

  • Motels (Score:2, Interesting)

    by Porchroof (726270)
    Every motel room should have one.

  • Hide submarines? (Score:3, Insightful)

    by barzok (26681) on Saturday January 12 2008, @09:19AM (#22013976)
    Just change how you look for them. Instead of looking for signature noise, look for a "hole" in the background noise of the ocean.

    • Re:Hide submarines? (Score:4, Informative)

      by thelamecamel (561865) on Saturday January 12 2008, @09:41AM (#22014132)
      Nup. The really cool thing about this device (for the light cloaking devices that have been built, anyway) is that you don't block the noise behind the submarine. However as I commented below, I don't think these devices would hide the noise of the submarine or whatever was within the cloak, they would just allow sound to pass through the cloaked submarine as if the submarine was not there. The other problem is that these cloaks only work for a limited frequency range.
    • That wouldn't be anything new. Although I can't provide references, I've heard from a number of sources that, late in the Cold War, US subs got to be too quiet and the Soviets did exactly as you suggested in order to find them.
    • WYIAAS. (Why Yes, I Am A Submariner, or at least I used to be.)

      Just change how you look for them. Instead of looking for signature noise, look for a "hole" in the background noise of the ocean.

      Except - that doesn't really work all that well in real life except when the submarine is very close to those who would like to detect it. Much, much closer than those trying to dectect the submarine actually want that submarine to be. The background noise in the ocean isn't stable enough to routinely depe

    • The Navy will need a new slogan: Silent But Deadly

      • That may already be happening. I've read that the Ohio-class subs are actually quieter than the surrounding sea when they're not moving, and the only thing giving them away is the "hole."

        That was a plot point in Clancy's The Sum of All Fears. The book contained a great deal of "technical detail" regarding submarines and the history of submarines. I have no idea how true any of it is (real specs would be classified above Top Secret), but it makes for interesting reading[1].

        [1] And of course the line "Sir, he couldn't lead a three year old to the crapper" is worth the price of the book all by itself.

  • The thumpa-thumpa (which neigbors are fond of)music is driving me nuts.
  • so us "normal" people don't have to put up with some inconsiderate &as%@d yapping away at 100dB in enclosed spaces about things that are so inconsequential they make you want to rip your ears off to escape the inanity of it all.

    If it needs a supermarket trolley to carry the equipment around in, well that's a small price to pay.

  • Not a cone of silence! (Score:5, Informative)

    by thelamecamel (561865) on Saturday January 12 2008, @09:37AM (#22014102)
    The devices the article talks about are not what you want from a cone of silence. What the researchers are proposing is something that will hide an object from external noises - as in the object will not affect any sound waves heading towards it, they will just pass straight through as if the object and cloaking device were not there. The proposed device WILL NOT contain noise created by whatever you're trying to hide, so the bad guys can still listen for a submarine's engines, they just won't be able to use active sonar to find the submarine.

    If you want a cone of silence, then you put yourself in a noise isolation chamber. Or if you want something cooler, then you put yourself in the acoustic equivalent of a gap-defect photonic crystal, which is a series of cylindrical rods arranged in a hexagonal lattice with one removed. A particular wavelength of sound will be reflected by this lattice, so if you're in the middle of that gap and you sing at that frequency, no-one outside the lattice will be able to hear you. Of course, you will very quickly become deaf because the sound is all reflected within the defect rather than absorbed, so the noise from your singing builds up.
  • Beware, this metamaterial could be the technology of flatulent terroristas! Silent and deadly...
  • There was one, and only one, sixties tv show that had the Cone of Silence, and if you don't know that, perhaps you should answer your shoe phone....

    On the microwave invisibility front, "hiding subs"? Reality check time: my wife, back in the early eighties, was in the "Hunt for Red October" command. All you need is a school of fish, or a cold water current, and the hunters can't find *anything*. Detecting subs is vastly over-pr'd, and under-possible.

              mark
    • No, a cone of silence [wikipedia.org] was first aired on television as part of George McFly's favorite TV program, Science Fiction Theater, episode "Barrier of Silence", written by Lou Huston and first airing September 3, 1955--10 years ahead of the NBC comedy. The original series Mission: Impossible also had an inverted form.

      In the series Get Smart the Cone of Silence only worked as intended once [wikipedia.org]: "However, at the end of the conversation, the Cone malfunctioned leaving the Chief trapped within, with silent screams of fru
  • Ahem, the fine article describes something that has quite a few limitations>:
    • It's a 2-D device. Hard enough to build it in 2-D. It's not clear it is even theoretically doable in 3D. Even if doable in theory, it may prove impossible to manufacture.
    • It only works for waves approaching it at a certain azimuth. Usually you need a much wider front.
    • These devices are hard to design, even for a limited frequency range. Visible light has less than a 2-1 frequency range, and that's likely to tax these de
  • This better not be part of an ARG for the upcoming Get Smart movie.

    • Isn't that something like a 2nd or 3rd level evocation spell? Amateurs!
      Nah, it's illusion not evocation. And even then, it's sphere-shaped [d20srd.org] while the article wants a cone.

      • Re: (Score:2, Informative)

        by Rob the Bold (788862)

        THe fact that you watched Get Smart in the '80s and '90s doesn't change the fact that this was a '60s television show!

        Sorry about that, Chief, I think he just meant that that was when he was a kid, not that he thought the show was produced in that era. It was syndicated a lot more heavily in those years than it is now, at least on any channel I have access to.

        I was just about to type that the series still wasn't available on DVD, but I checked Amazon and I was wrong, it finally is: http://www.amazon.com [amazon.com]

        • I was just about to type that the series still wasn't available on DVD, but I checked Amazon and I was wrong, it finally is:

          Actually it's been available directly from Time Life Video [timelife.com] for awhile for a lot less, but also still quite expensive. I already have the full series box set (and automatically on their e-mail list). They have exclusive rights to sell it for now [wikipedia.org], but it should become available from others quite soon (longer for Region 2). The listings on Amazon are people reselling it; none of them are sold by Amazon (notice no Preorder options).

          The movie The Nude Bomb [imdb.com] can be found on cable as "The Return of Maxwell Smar

          • The movie The Nude Bomb can be found on cable as "The Return of Maxwell Smart". I have it sitting on my TiVo recorded in HD waiting for me to do a capture of it downcoverted

            Completist or glutton for punishment? ;)

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