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Earth Science

Earthquake Invisibility Cloak 121

BuzzSkyline writes "The same folks who brought us the tsunami invisibility cloak last year have now come up with an earthquake invisibility cloak. They show that a platform made of just the right configuration of elastic rings could make a structure invisible to earthquakes by effectively steering a quake around the structure. It doesn't work well for compression waves, but the researchers claim it could hide buildings from the slower-moving, more destructive shear earthquake waves. The research is due to be published soon in the journal Physical Review Letters."
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Earthquake Invisibility Cloak

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  • by florescent_beige ( 608235 ) on Sunday July 19, 2009 @11:17AM (#28748165) Journal
    If you're in marketing you call it an invisibility cloak. If you're an engineer you call it a tuned resonator and ask yourself why oh why you didn't go to medical school.
    • Guenneau said that it's possible to shield an object, even a building, so that an incoming earthquake wave behaves as if the object weren't there. The building in the path of the wave is like a rock in a fast-flowing river, he said.

      Having seen my share of rivers, I can pretty much say that the water pattern DOES change when it hits a rock.

      And that the rock is more solid than the water.

      With an earthquake, isn't the building less solid than than Earth?

      "It's the same picture, the wave pattern, as for a water w


      • Maybe their technology does work, but their analogies do not.

        It's an analogy, not a model. Analogies are always their to bridge the gap between complete ignorance and knowledge. Grasping onto the analogy and complaining it doesn't work is like floating while holding onto a life preserver while trying to cross a stream and complaining the life preserver isn't getting you to the other side.

        In other words, if you want to understand what's going on you need to start understanding the model and throw away the

        • Re: (Score:1, Funny)

          by Anonymous Coward

          Whenever I hear the word activist, I reach for my revolver.

          I'm a gun-rights activist. What do you do now?

        • In other words, if you want to understand what's going on you need to start understanding the model and throw away the dumb analogy.

          So what you're saying is, it would be easier to get to the other side of the river if you just threw the life preserver away? ;)

      • Re: (Score:2, Interesting)

        by jonadab ( 583620 )
        > With an earthquake, isn't the building less solid than than Earth?

        Solidity isn't necessarily good protection against an earthquake. A hunk of granite bedrock a mile thick is a fairly solid thing, but a medium-grade earthquake will crack it without breaking a sweat. The atmosphere, on the other hand, is not generally considered to be solid, but it's difficult to imagine an earthquake powerful enough to damage it.
      • Maybe their technology does work, but their analogies do not.

        Yeah, where's the car?

      • Re: (Score:3, Informative)

        by Bandman ( 86149 )

        > With an earthquake, isn't the building less solid than than Earth?

        IANASiesmologist (but I play one on TV (ok, I can't back that up))

        Actually, sometimes it isn't. Depending on the properties of the quake (strength, depth, etc), the ground itself (particularly soil) acts a lot like a liquid. A "slab" house might float while a bedrock based building may have major structural issues due to compression of the major structural elements. This is one of the big reasons that building in earthquake zones have "f

    • Re: (Score:3, Interesting)

      by cduffy ( 652 )

      An informal survey done my one of my coworkers at a party with his fiance's family and coworkers (a group largely composed of doctors and lawyers -- she's doing her residency) found that only 25% of the doctors would do it again (given the costs and stresses involved); many indicated they'd have stayed in medicine, but have gone for a cheaper job title (such as FNP). For the lawyers, the would-do-it-again ratio was closer to 50%.

      I think we engineers have it good.

      • by vux984 ( 928602 ) on Sunday July 19, 2009 @11:47AM (#28748331)

        I think we engineers have it good.

        Many doctors and lawyers go into the field for the money. That's not really true of the hard science/engineer types. So most engineers would do it again because they actually want to spend their time engineering, and enjoy it.

        That's true of a lot of doctors too...but a lot of them just picked their career by the expected income. How many engineers or mathematicians or computing scientists or physicists etc chose the career for the paycheque*. Sure we can get paid well, but lets face it... its not the license to print money being a lawyer or doctor can be.

        (*Other than the brief rash of worthless eng. and comp.sci. grads chasing the .com bubble)

        • Re: (Score:2, Interesting)

          by Anonymous Coward
          Many doctors and lawyers go into the field for the money.

          And doctors going into it for the money is one of the big reasons why healthcare is so broken in America. Doctors aren't doing it in order to help people (though it is a secondary motive for some). Rather, they're mainly doing it to enrich themselves. Is it any surprise that healthcare is so expensive?
          • Re: (Score:2, Interesting)

            by martas ( 1439879 )
            if there is such a difference of incentives between US doctors and, say, Canadian doctors, then i find it hard to believe that that is the root cause of the problem. rather, i think it's probably much more of a consequence.
        • by martas ( 1439879 )
          unless you're really awesome, and patent something that ends up earning you millions. it's happened before, but unfortunately for me it's pretty rare in CS.
    • by Dunbal ( 464142 )

      and ask yourself why oh why you didn't go to medical school.

            And AFTER the earthquake, you will ask yourself why oh why DID you go to medical school...

    • If you're an engineer you call it a tuned resonator...

      Not necessarily. One other way to make a building "invisible" to the shear waves of an Earthquake would be to float it. Shear waves cannot pass through liquids. Of course this is probably somewhat less practical...

    • by Abreu ( 173023 )

      Instead of Invisibility Cloak, I would call it "Earthquake Deflector Shield"

      Same coolness, more accuracy

    • I never thought I'd SEE a tuned resonator, let alone create one...
    • as a bioengineering graduate now in med school, i frequently ask myself "why didnt i stay in engineering?" ymmv
  • by wjh31 ( 1372867 ) on Sunday July 19, 2009 @11:25AM (#28748203) Homepage
    we have enough trouble predicting when they will come as it is, if you make them invisible we wont stand a chance.
  • by girlintraining ( 1395911 ) on Sunday July 19, 2009 @11:26AM (#28748215)

    It's not an invisibility cloak. A nearby building could still fall on the cloaked one, with the usual result. Also, it's not a cloak, as in a piece of fabric. Last, anything can be made resistant to earthquakes, but to make it earthquake-proof is something only an arrogant designer or a project manager would say. Every design component can fail, and most catastrophic engineering failures are rooted in miscalculation or failing to test the model with a particular cascade of failures.

    • Actually, I'm pretty sure those arrogant designers at NASA are quite confident that the International Space Station resists earthquakes.

      For the more terrestrially minded, the problem is to resist earthquakes in a cost effective manner, or alternatively stop people from doing stupid things. After all, why do people knowingly locate in known flood areas behind dikes, in arid deserts, underneath volcanoes, or in known high-intensity earthquake areas? and not expect disasters to happen?

      Live in the big flat m

      • by Dunbal ( 464142 ) on Sunday July 19, 2009 @11:59AM (#28748409)

        Live in the big flat mid-west plains, it might be boring, but it is safe.

              (Taps Cassini2 on the shoulder and points to the huge tornado) "Is anywhere safe?"

        • by GigsVT ( 208848 )

          Central/Western VA, WV, TN, KY... those are all pretty immune to most natural disasters. Hurricanes are all petered out by the time they hit here, the biggest earthquakes are like magnitude 4, the mountains kill the tornados quickly in general, there are no big rivers that cause massive flooding, etc.

          • My part of TN, we have the occasional tornado. F2s. No big ones so far in over 200 years of settlement. One tornado fatality in the last 20 years within a 50 mile radius, and there's claims the wall which fell there was single thickness brick constructed by the amateur homeowner. Floods? My home is over 500 feet above the local river. Earthquakes? If the new Madrid fault lets loose and literally hits Memphis TN with a Richter 10.8 quake and not a building is left in pieces bigger than marble sized, I would

        • Re: (Score:3, Funny)

          Taps Cassini2 on the shoulder and points to the huge tornado "Is anywhere safe?"

          Cassini: Ah, I'm sorry, but I'm over 746 million miles away right now. Try asking a satellite a bit closer.

      • Live in the big flat mid-west plains, it might be boring, but it is safe.

        As long as you're not near New Madrid, MO.

      • by egburr ( 141740 )

        Live in the big flat mid-west plains, it might be boring, but it is safe.

        ... till the tornadoes come through.

      • The ISS doesn't resist earthquakes, it simply isn't subjected to them.

      • Actually, I'm pretty sure those arrogant designers at NASA are quite confident that the International Space Station resists earthquakes.

        And it would be just like them to focus on earthquakes, which can't happen in space, instead of say, solar flares.

        the problem is to resist earthquakes in a cost effective manner, or alternatively stop people from doing stupid things.

        Well, the second half of that is clearly impossible, so I'd suggest focusing on cost efficiency.

        why do people knowingly locate in known flood areas behind dikes, in arid deserts, underneath volcanoes, or in known high-intensity earthquake areas

        Curiously, the most fertile land, plentiful sources of water, and temperate climates, are located in those places. Except underneath volcanoes -- evil overlords live there, not joe average.

        and not expect disasters to happen?

        Oh, I think they do expect disasters to happen. And everyone else to pay for it thanks to this con game we call "

    • Also, it's not a cloak, as in a piece of fabric.

      Fabric, I think you're on to something there. Maybe they're selling tents? I guess they'd be pretty good in an earthquake. In fact, they seem quite popular afterwards, so just save time and live in one to start with.

  • by VincenzoRomano ( 881055 ) on Sunday July 19, 2009 @11:27AM (#28748223) Homepage Journal
    What will happen when all buildings in a certain area will be "cloaked" to earthquakes?
    Will mechanical waves skip the entire area?
    What if all buildings in a certain large area will be made that way?
    I fear that the "solution" is good only when a few of them are made that way. The other ones will need to collapse.
    • by OrigamiMarie ( 1501451 ) on Sunday July 19, 2009 @11:41AM (#28748307)
      It should be perfectly safe to cloak all buildings. Buildings only absorb a tiny fraction of the shock of an earthquake; you don't need to have something man-made fall over just to keep the waves from going further. Now if you somehow made huge chunks of land cloaked to earthquakes, I would agree that the shaking may have to come out somewhere. But anyway at that point you're talking about making an isolated chunk of land whose borders crunch and stretch a lot more than everything else -- people wouldn't go for that. And I don't see how you'd do it anyway, you can't just seismically isolate a chunk of land.
    • Re: (Score:2, Funny)

      Comment removed based on user account deletion
      • We're working on this. We've got this perfected for cars, we just need to perfect the bigger hydraulic cylinders needed for buildings.

    • by Manchot ( 847225 )
      The way that all invisibility cloaks work (at least theoretically) is that you create a structure whose materials parameters vary in such a way that it effectively performs a coordinate transformation, mapping points in the cloaked region to points outside of it. In real space, the wave curves around the object, but in transformed space, it still travels in a straight line. For electromagnetic cloaks, it is the permittivity (refractive index squared) of the structure that is engineered. I don't know much ab
  • Retrofitting (Score:1, Insightful)

    It would be much more useful if this technology could be retrofitted onto older buildings.
  • But is it effective versus the Juggernaut?
  • Flying (Score:4, Funny)

    by bertoelcon ( 1557907 ) on Sunday July 19, 2009 @11:51AM (#28748373)
    Does this render you invincible to ground pokemon, that is unless they use non-ground attacks?
  • by Kenshin ( 43036 ) <.kenshin. .at. .lunarworks.ca.> on Sunday July 19, 2009 @01:52PM (#28749099) Homepage

    Good thing we invented the earthquake invisibility cloak! Now the earthquakes won't be able to see me!

  • Wind Cloak? (Score:2, Interesting)

    by Anonymous Coward

    IANAP but the basic idea I got from the design of the "Tsunami Cloak" was that there was simply a path of less resistance along the concentric corridors than along the radial ones, so that the wave tended to flow around the center rather than through it. Correct me if I'm wrong about this. Sometime later I was wondering if the same principal could be used to redirect strong winds around a vulnerable structure. I was thing along the lines of metal posts rather than concrete pillars, but then I started consi

    • by baegucb ( 18706 )

      This is how a snow fence works. It doesn't stop the snow from piling up, it re-directs the wind blowing the snow.

  • you keep using that word. i don't think it means what you think it means.

  • Wouldn't the intensity of the waves be concentrated around the periphery of the rings? Would two or more earthquake shields in particular arrangements have a focusing effect, unwittingly completely leveling a nearby building from a otherwise mild shake?
  • Earthquake Invisibility Cloak
    Enchantment
    {1}{R}
    All creatures have flying.
    • If only. All this thing does is give all creatures protection from Earthquake, which makes it somewhat pointless. They should've worked on a generic protection from red.
  • ...the epicenter of the quake is *inside* the ring? Imagine a future skyscraper with a huge base and this installed.
    Now imagine a quake in the middle of that protective ring. Would the waves reflect off the inside, ripping the building apart in seconds?

    That would be one giant nelson munz "haah-haaah" moment. (Except for the people in the building!!)

Think of it! With VLSI we can pack 100 ENIACs in 1 sq. cm.!

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