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Tsunami Invisibility Cloak

Posted by ScuttleMonkey on Mon Sep 29, 2008 06:11 PM
from the just-deflect-those-waves-to-the-poor-town-next-door dept.
BuzzSkyline writes "New Scientist is reporting on a lab-scale experiment that may lead to a tsunami invisibility cloak, which could protect islands, open-ocean platforms and even coastlines from dangerous waves by effectively making them invisible to tsunamis. The technology is based on the same sorts of negative index of refraction ideas that some physicists are exploring as they try to make an optical invisibility cloak, except that it works with water instead of light."
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story

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[+] News: The Largest Recorded Tsunami Was 50 Years Ago 323 comments
An anonymous reader writes "July marks the 50th anniversary of the world's largest tsunami — a 1,720-foot-tall wave in Lituya Bay, Alaska. It was triggered by a chain reaction of events that began with a magnitude 7.7 earthquake on the Fairweather Fault, which dislodged a rock fall of 40 million cubic yards, that fell 3,000 feet and splashed into the northwest end of Lituya Bay to generate the wave. This article includes survivor accounts, maps, a satellite image, and photos taken right after the event." To be fair, eyewitness accounts put the height of the wave as it came toward their boats at perhaps 100 feet. The tsunami scoured the land of vegetation and soil to a height of 1,720 feet above sea level, however.
[+] Technology: Scientists Closer To Invisibility Cloak 308 comments
Aviran was one of many readers to submit news of a just-announced development in the ongoing quest to develop a working invisibility cloak, writing: "Scientists say they are a step closer to developing materials that could render people and objects invisible. Researchers have demonstrated for the first time they were able to cloak three-dimensional objects using artificially engineered materials that redirect light around the objects. Previously, they only have been able to cloak very thin two-dimensional objects" Reader bensafrickingenius adds a link to coverage at the Times Online, and notes that "the world's two leading scientific journals, Science and Nature, are expected to report the results this week." Tjeerd adds a link to a Reuters' story carried by Scientific American.
[+] News: Earthquake Invisibility Cloak 121 comments
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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  • by Anonymous Coward on Monday September 29 2008, @06:14PM (#25198739)

    Notice when the Island moved at the end of last year? What date was it? What happened around that time? Tsunami.

  • by Anonymous Coward on Monday September 29 2008, @06:14PM (#25198741)

    Move along - Nothing to see here.

  • And invisibility will help you against a giant wave? I wasn't aware that Tsunamis basically hunted those vulnerable islands and coastlines down for large scale destruction.
    • by Thomas M Hughes (463951) on Monday September 29 2008, @06:24PM (#25198869)

      I know the wording is awkward. But, keep in mind, light is understood to be a wave as well. Thus, the mechanic of causing a tsunami to go seamlessly around an island should be nearly the same as causing a light beam to go around the object. This wouldn't block the Tsunami wave, the wave would continue as normal, as if nothing had happened. The Island also would not be touched by the wave either. The metaphor seems to work.

        • by Thomas M Hughes (463951) on Monday September 29 2008, @06:36PM (#25198999)
          Not exactly. When you're invisible, the light simply passes through where you would have been as normal. You're just not in the way to block those waves anymore. According to the article, the water from the Tsunami mostly goes straight through as if the island wasn't even there. So, if there is a wave that originates from the east, it hits this cloak, the wave will continue it's movement west as if it never hit an island at all. The only ones who would be affected would be anyone who's behind that island, who has been using it to break their Tsunamis in the past.

          Having said that, I'm not entirely clear how you can use the device described to protect coastlines. It looks like you need a 360 degree coverage for the device to work. That's not going to work for something like say...China's coast.
          • by pushing-robot (1037830) on Monday September 29 2008, @06:43PM (#25199107)

            Having said that, I'm not entirely clear how you can use the device described to protect coastlines. It looks like you need a 360 degree coverage for the device to work. That's not going to work for something like say...China's coast.

            I think it could be made to work... but it would suck to be in Iceland.

              • by tbannist (230135) on Tuesday September 30 2008, @09:57AM (#25204079)

                Not really, their point is pretty good. If a Tsunami would have broken up on your island, the "invisibility" rings will instead pass it on to the guy behind you.

                Of course, a better analogy of why that has to be acceptable is that, you can't be held liable if you duck and the guy behind you gets shot. It's not your fault that he was unwilling or unable to duck too.

        • by MidnightBrewer (97195) on Monday September 29 2008, @06:47PM (#25199147)

          I was thinking this, too. However, if you read the article, it's intended for man-made structures and, if you look at the model (and read the article), it doesn't seem like it'd be feasible for anything on a larger scale, anyway. You'd end up destroying most of your own coastline and aquatic habitat in the process, and seriously screwing up the local ocean pretty much permanently.

    • And invisibility will help you against a giant wave? I wasn't aware that Tsunamis basically hunted those vulnerable islands and coastlines down for large scale destruction.

      Well they tried giant towels, figuring that the Tsunami would think that since the Island couldn't see it, then it must not be able to see the Island, but that didn't work because Tsunami's are far to clever for that. Which isn't too surprising since Tsunami's are proven pack hunters, always attacking in waves.
  • From the article:

    But Guenneau cautions that large structures like islands and coastlines are unlikely to become invisible anytime soon, because building the many small islands needed to protect one is such a big job.

    "It's crazy - maybe only people in Dubai could do this," he adds, referring to the spectacular artificial islands built there.

    Smaller structures such as offshore oil platforms would be easier to protect, he says.

    No, we are not going to be protecting islands with this thing anytime soon. And we're not protecting tsunamis from anything because the tsunami will just wash over this suckers unless we build them really, really tall. In which case, we're better off building a freaking wall.

  • Okay... but... (Score:4, Interesting)

    by mattsgotredhair (945945) on Monday September 29 2008, @06:20PM (#25198807) Journal
    how do you end up getting ships in and out of the coast?
    • by evilviper (135110) on Monday September 29 2008, @07:29PM (#25199571) Journal

      how do you end up getting ships in and out of the coast?

      First, you draw this tsunami-wave canceling device on a placemat, labeling the ocean as "START" and the coastline as "FINISH". Print out thousands of them and hand out the placemats to family restaurants, along with a few boxes of crayons.

      Then, you just go around collecting the "used" placemats, kindly filled out by unsuspecting 5 year-olds, and deliver them to cargo-ship captains.

      Problem solved.

  • Feasibility (Score:5, Informative)

    by fiannaFailMan (702447) on Monday September 29 2008, @06:21PM (#25198817) Journal

    Quoth TFA:

    But Guenneau cautions that large structures like islands and coastlines are unlikely to become invisible anytime soon, because building the many small islands needed to protect one is such a big job.


    "It's crazy â" maybe only people in Dubai could do this," he adds, referring to the spectacular artificial islands built there.


    Smaller structures such as offshore oil platforms would be easier to protect, he says.

    It's a nice idea but a barrier like this would have to be made of strong stuff. That Asian tsunami a few years ago was able to pick up ten-feet-tall concrete blocks and throw them around like Lego bricks. I'm not sure if I'd want to be sitting downstream of something like this unless they're thinking of making them out of low-lying artificial islands, and in that case I don't know how effective they'd be under a tall enough wave. I'd like to have seen a bit more in the way of diagrams and specifics in TFA.

  • Jeez (Score:5, Funny)

    by atomicthumbs (824207) <atomicthumbs.gmail@com> on Monday September 29 2008, @06:22PM (#25198829) Homepage
    What's wrong with these scientists? Why work on making tsunamis invisible when we have enough trouble with the ordinary, visible ones already?
  • Waterhenge! (Score:5, Funny)

    by MaxwellEdison (1368785) on Monday September 29 2008, @06:22PM (#25198833)
    Anyone else notice that their scale model looked an awful lot like a certain circle of monolithic stones? We know the technology works. When was the last time Britain was hit by a tsunami?
  • by apodyopsis (1048476) on Monday September 29 2008, @06:25PM (#25198883)
    early warning system is much cheap then numerous artificial islands.

    rebuilding is much cheaper then numerous artificial islands.

    most people will detect, warn, evacuate and rebuild - this kind of (very very) expensive prevention simply does not make sense on a 1 in 100 year (if not much more) disaster prevention.

    it is like putting in bullet proof glass in all the windows of your house just in case the couple next door decide to have a son who might want to buy a bb gun later on in life...
    • by srothroc (733160) on Monday September 29 2008, @06:36PM (#25199003)
      The Netherlands have various kinds of incredibly costly structures erected to prevent those 1 in 100 year events that you seem to scoff at. Sure, they could just sit around waiting for one to happen and clean up after the mess by pumping out the water and holding it back again after a flood, but I doubt anyone would really want to live there knowing that it could happen to their grandkids because the government was too cheap to protect them.
    • by Chris Burke (6130) on Monday September 29 2008, @06:46PM (#25199129) Homepage

      early warning system is much cheap then numerous artificial islands.

      Definitely.

      rebuilding is much cheaper then numerous artificial islands.

      most people will detect, warn, evacuate and rebuild - this kind of (very very) expensive prevention simply does not make sense on a 1 in 100 year (if not much more) disaster prevention.

      Er, well, that's not so clear. I mean that was roughly the logic behind not building up the levies in New Orleans, and the cost of that project was several times less than the resulting damages from Katrina. A project which they are now engaging in so as to prevent a subsequent disaster and make people feel safe returning to/investing in the city, meaning they payed for the protection but had to also pay much, much more due to not having it when they needed it.

      Now I'm not saying this particular system is cost effective for any particular city. I think it would mostly depend on what kind of materials and engineering you need to make effective barriers. These aren't artificial islands like the ones in Dubai the article mentions. They're big walls. If a tall column of reinforced concrete sunk into the ocean floor, like the struts of a large suspension bridge, is sufficient then I don't think it would be that ridiculous. And think of it this way -- just because "the big one" only comes once every hundred years, there's still plenty of "pretty big ones" that cause lots of damage every single year.

      it is like putting in bullet proof glass in all the windows of your house just in case the couple next door decide to have a son who might want to buy a bb gun later on in life...

      If I may engage in some analogy abuse, it's more like the couple next door has a son who pretty consistently fires off a few rounds in random directions every night, sometimes using larger calibers than others. How long are you going to bet that he hits someone else's house and not yours? It probably sounds like a safe gamble up to the point the .45 flies through your living room.

      Hurricanes, typhoons, and tsunamis happen regularly. They hit sections of the coast every year, causing damage every time. They aren't hypothetical. Even the big ones aren't. They're more like matters of probability, and thus time.

  • by CopaceticOpus (965603) on Monday September 29 2008, @06:47PM (#25199151)

    If you can't see the tsunami, the tsunami can't see you.

    • Re:well... (Score:5, Insightful)

      by darthwader (130012) on Monday September 29 2008, @07:07PM (#25199331) Homepage

      Note that the Netherlands is not under water, and all those man-made lakes behind dams have not all drained. And when it comes to warming up the planet by adding CO2 to the atmosphere, Science has done a great job against nature. When science fights nature, science generally wins, but nature does always get a few really good hits in first.

      The idea from TFA is not to use additional energy to hinder the tsunami, but to merely redirect the tsunami's energy. It's like the Judo of climate control. If I understand the article correctly, the posts do not have to be strong enough to stop the tsunami. That's the entire point of it.