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Metamaterials Developed To Bend Sound Waves, Deflect Tsunamis

cold fjord writes in with this story about some new possible applications for metamaterials. "A new way of assembling things, called metamaterials, may in the not too distant future help to protect a building from earthquakes by bending seismic waves around it. Similarly, tsunami waves could be bent around towns, and sound waves bent around a room to make it soundproof. ... Metamaterials are simply materials that exhibit properties not found in nature, such as the way they absorb or reflect light. The key is in how they're made. By assembling the material — from photonic crystals to wire and foam — at a scale smaller than the length of the wave you're seeking to manipulate, the wave can, in theory, be bent to will. ... Ong and others say ... they could be used to redirect other kinds of waves, including mechanical waves such as sound and ocean waves. French researchers earlier this year, for example, diverted seismic waves around specially placed holes in the ground, reflecting the waves backward. Ong points to the possibility of using what has been learned in reconfiguring the geometry of materials to divert tsunamis from strategic buildings.'"

110 comments

  1. Tsunami "Bending" can't work by BoRegardless · · Score: 1, Insightful

    You are talking about redirecting amounts of energy in a wall of water than may be 10-20 feet high or more, yet it comes in as a solid wave and the elevation stays at that height causing water to move inland extremely fast for a long time.

    It would be easy to calculate what amount of energy that would be in a width of a town: E = .5 * mass x v^2. You are talking about amounts of energy that would dwarf anything a major multi-unit power plant could produce.

    1. Re:Tsunami "Bending" can't work by cold+fjord · · Score: 4, Informative

      You are talking about redirecting amounts of energy in a wall of water than may be 10-20 feet high or more, yet it comes in as a solid wave and the elevation stays at that height causing water to move inland extremely fast for a long time.

      It would be easy to calculate what amount of energy that would be in a width of a town: E = .5 * mass x v^2. You are talking about amounts of energy that would dwarf anything a major multi-unit power plant could produce.

      Some scientists working with this sort of approach seem to think there is some potential for handling seismic energy.

      How to Repel an Earthquake

      "It's very cool stuff," says Ulf Leonhardt, a theoretical physicist at the University of St. Andrews in the United Kingdom who was not involved with the study. "It's a step toward manipulating seismic waves and done in a genius way." ...

      The scientists created their jumbo-sized metamaterial in August 2012 by drilling holes in a thick bed of silt and clay near the city of Grenoble in the French Alps. The cylindrical holes stretched down about 5 meters into the earth, but were also skinny, only 32 centimeters wide. They were arranged in a rectangular grid of three rows of 10 holes each. The holes changed the density and stiffness of the earth and, thus, the speed and direction of vibrations rippling through the ground, forming a seismic metamaterial. The scientists then shook the earth on one side of the grid using a vibrating soil-compacting machine that they had placed underground. That machine created 50 seismic surface waves per second with a wavelength of 1.56 meters—about the same as the distance between the holes, though shorter than typical wavelengths from earthquakes.

      Sensors placed throughout the site showed that the waves couldn't get past the grid of holes, bouncing off of it instead, the researchers report in a paper posted on the arXiv online preprint server. The waves just barely got by the second row of holes and couldn't even touch the third row, leaving the ground on the other side unshaken.

      --
      much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
    2. Re:Tsunami "Bending" can't work by Thanshin · · Score: 3, Funny

      Because, as we all know, if you deal with a really large amount of energy, physics can't possibly work.

    3. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      yeah...let's just bounce an earthquake. whatcouldpossiblygowrong. "very cool stuff" indeed

    4. Re:Tsunami "Bending" can't work by TubeSteak · · Score: 2

      Can you walk through walls? Become invisible? Bend tsunamis?
      Hang on for a shocking discovery that will rock your world!
      One little trick that can hack physics!
      Click here to find out how!

      --
      [Fuck Beta]
      o0t!
    5. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      Aaaand that was the joke.

    6. Re:Tsunami "Bending" can't work by dbIII · · Score: 1

      Can you walk through walls

      Yes - damn those termites!

      Become invisible

      Yes - dark in here isn't it?

      Bend tsunamis

      No, but that city it washed over diverted the flow. Maybe doing something like the physical features that diverted the flow can be exploited to divert another one so it could do less damage. If only there was an article about such a thing.

      Science! It works bitches!


      They said antigravity would never work, but then they had not yet met Elisha Otis's Elevator!
      In other words if you haven't worked it out yet from the above you don't have to meet something head on to solve the problem.

    7. Re:Tsunami "Bending" can't work by LordLimecat · · Score: 1

      Dude, what dont you understand? Metamaterials can bends soundwaves, tsunamis are just big waves, therefore metamaterials can bend tsunamis.

      SCIENCE!

    8. Re:Tsunami "Bending" can't work by LordLimecat · · Score: 1

      Are you aware that the tsunami which generated the 2011 Japan tsunami occurred out in the middle of the ocean?

      Its not the seismic activity you need to stop, its the wall of water caused by said seismic activity.

    9. Re:Tsunami "Bending" can't work by VortexCortex · · Score: 1

      "Can you walk through walls?" Yep. Doors exist. "Become invisible?" Turn off the light. "Bend tsunamis?" Build a sandbar.

      "Hang on for a shocking discovery that will rock your world!" Nope. A rolling stone gathers no moss.

      "One little trick that can hack physics!" Physicists Hate This One Weird Trick!

    10. Re:Tsunami "Bending" can't work by fatphil · · Score: 2, Informative

      Yeah, but the solution to the problem in high energy physics is to make sure the high energy things don't touch anything important.

      So, in this case, all we need to do is to levitate the ocean.

      And you do realise that the mass of these pulses that LHC is trying to bend is only a tenth of a millionth of a gram? Tsunamis weigh quite a bit more than that.

      But jesting aside, the article does look mostly bullshit, as it's highly inappropriate to model tsunamis as waves and solutions as working upon waves. They're so low frequency they're effectively DC. That's why in the term "tidal wave" is inappropriate - the "tidal" part is fine - in fact, it's almost perfect - it's the "wave" part that's misleading.

      --
      Also FatPhil on SoylentNews, id 863
    11. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      It would be easy to calculate what amount of energy that would be in a width of a town: E = .5 * mass x v^2.

      You only need that much energy if you intend to stop the wave. They want to divert the wave, which takes only a fraction of that energy.

    12. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      I think the biggest problem is that the biggest damage from a tsunami is not caused by the waves.
      Its caused by the load of debris it carriers with it. Maybe this thing can reduce or even deflect the wave strength. But if you plan to only position it around strategic buildings, the debris the waves was carrying will still crash into it.

      Then there is still the problem that it deflects the waves. It doesn't diminish them. So any areas around it are going to get hit even harder.

    13. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      If you have a 30 meters metawall you also might have a stronger normal 30 meters wall... Deflecting a tsunami does not seem reasonable, treating it like a normal wave, as an earthquake, does not seem reasonable either if you have seen a class or two of fluid mechanics. On the other hand, earthquakes can be deflected with something around a building, there's a lot of research in that matter.

    14. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 1

      But jesting aside, the article does look mostly bullshit, as it's highly inappropriate to model tsunamis as waves and solutions as working upon waves. They're so low frequency they're effectively DC. That's why in the term "tidal wave" is inappropriate - the "tidal" part is fine - in fact, it's almost perfect - it's the "wave" part that's misleading.

      No, this is BS right here. Considering for some time there have been well developed models of tsunamis used to predict potential dangers and setup tsunami warnings, treating the tsunamis as waves. Their wavelength may be quite long, and knowing what a soliton is might help, but they are still waves.

      And the reason researchers think the term tidal wave is inappropriate has everything to do with the word "tidal" which is the opposite of perfect, since tsunamis have little to nothing to do with tides. If you want tidal waves, you can see them every day in the Bay of Fundy.

    15. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      yeah...let's just bounce an earthquake. whatcouldpossiblygowrong. "very cool stuff" indeed

      Well.. consider this kind out structure protecting the Fujinuma Dam back in 2011.
      Worst case scenario would probably have been that the protection wouldn't have worked at all and the dam burst just like it actually did, leading to flooding of homes and death of a bunch of people.
      Normal case scenario would have been that the earthquake was reflected to some less critical area.

      The idea isn't to reflect earthquakes all around randomly but to protect important sites where a failure would lead to larger damages. In particular water dams are extremely vulnerable to earthquakes and causes by far the most deaths among all power sources.
      Causing the earthquake to be stronger in a nearby village is generally a preferable option. People often have plenty of time to get out of their houses and get to safer locations. Escaping a dam breach is a lot more problematic and the water will not only destroy the houses but also a lot of the appliances in the homes. (Yep, you can often dig out your porn collection after an earthquake. After a dam breach everything is destroyed.)

    16. Re:Tsunami "Bending" can't work by cold+fjord · · Score: 1

      Yes, I'm aware. But the parent post was commenting on the amount of energy required. Wouldn't the energy of the tsunami be comparable to the event that created it? If seismic energy is manageable despite the magnitude then I would expect that the energy of a tsunami would be manageable, but the form would obviously be different. It may be that the form renders it infeasible, just not the magnitude.

      --
      much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
    17. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      Their wavelength may be quite long, and knowing what a soliton is might help, but they are still waves.

      Knowing that solitons don't exist for water waves, and that we've known that solitary waves are a poor model for tsunamis for decades, may help even more.

    18. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      Build a sandbar.

      Then what? They move, you know.

    19. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      Solitons were first observed in water waves, and exist as a solution to several of the approximate models used to model water waves. Depending on what exact system and scale you are looking at, the deviations from those models may be insignificant. Even when the deviations from those become more significant, you end up with effective soliton like behavior.

    20. Re:Tsunami "Bending" can't work by fatphil · · Score: 1

      You're confusing "actually tides" and "like tides". The closest thing to a tsunami is a tide. Tsunamis are about as tidal as you can get without actually being tides.

      Yes, you can model the uninterrupted propagation of tsunamis as waves. Yes, you can model the diffraction around island-sided opjects as waves. Yes, you can model the propagation of tsunamis down channels as waves, solitons as you say. But no, humans cannot realisitically use meta-material approaches to modifying tsunamis in order to protect against them.

      Unless you can build *island-sized* features. The wavelenth is 500-1000km. The meta-material needs features with a size comparable to that of the wavelenth in order to affect wave-like behaviour in the ways being talked about. We do not have the capability to build such structures. I've not read the particular research the article refers to, but I presume it's to do with the negative refractive index lens. That permits you to create a shadow (i.e. shield what is behind) which is larger than the object itself. (So in theory, small things could protect an island.) However, in order to do that, you have to build a metamaterial structure the size of the shadow you wish to create. That's not a win. It's a massive loss, as now you have to build a huge fancy thing rather than a huge dumb thing.

      --
      Also FatPhil on SoylentNews, id 863
    21. Re:Tsunami "Bending" can't work by Anonymous Coward · · Score: 0

      You've changed your argument to something completely different. There wouldn't have been an issue in the first place if you talked about scale size being an issue as other posters had already, but instead you went someplace completely incorrect by saying tsunamis can't be modeled as waves. You might as well have said that radio waves aren't waves because antennas don't have infinite bandwidth. "as it's highly inappropriate to model tsunamis as waves and solutions as working upon waves" is not correct at all.

      And you're still completely backwards about the meaning of tidal wave and why it pisses off researchers and scientists working in related fields. There are actual waves created by tides, some of which can be quite big, although now the accepted term is tidal bore because people get too confused when using the term tidal wave. This is stuff that shows up in lower grade level exercises and science classes these days. "Tsunamis, sometimes erroneously called tidal waves, are ocean waves..." should be a hint the issue is not with calling it a wave.

    22. Re:Tsunami "Bending" can't work by sjames · · Score: 1

      I can redirect the energy of a 4000 pound vehicle doing 75MPH with only my little finger. It's just a matter of where and how the force is applied. Remember, the objective isn't to counter the energy, it's to redirect it a bit.

    23. Re:Tsunami "Bending" can't work by fatphil · · Score: 1

      My post was supposed to be read in the context of using focussing on metamaterial approaches. I.e. what this story is about. If you forget the context of the story, then my post makes less sense. The problem has always been scale, as metamaterials work at the scale of the wave, and the scale of these waves is mind-bogglingly huge. Therefore it's inappropriate to try and process the wave behaviour in order to solve the problem of the bulk matter.

      Your completely backwards about why tidal waves were named that way. They were named that way as they were tide-like in effect. The name is appropriate. If you start saying "but they're not caused by tides", then you deserve the response "nobody said they were, fool". If you stop deliberately misinterpretting things, you'll have a lot less stressful life. You probably think that my weight should only be measured in Newtons rather than kilograms, don't you? If so, yet again, you'd be wrong.

      --
      Also FatPhil on SoylentNews, id 863
  2. cold fjord and "metamaterials" by Anonymous Coward · · Score: 0

    Betcha he was looking for an NSA story there

    1. Re:cold fjord and "metamaterials" by Anonymous Coward · · Score: 0

      Nah, probably looking for drugs to help the obsessive compulsives that have to bring up NSA in every story regardless of the topic. You might be a candidate, for example. Talk to your doctor and ask if one of these treatments is right for you.

  3. Re:5 Minutes of Computer Time by PPH · · Score: 4, Funny

    But now, thanks to metamaterials, we don't have to listen to your screams.

    --
    Have gnu, will travel.
  4. Force fields? by Anonymous Coward · · Score: 0

    Not gonna happen in this life time.

    1. Re:Force fields? by Thanshin · · Score: 1

      There's nothing shameful on being old.

  5. divert tsunamis from strategic buildings by Anonymous Coward · · Score: 2, Insightful

    and towards some poor fishing village full of primitive natives nobody cares about..

    1. Re:divert tsunamis from strategic buildings by Anonymous Coward · · Score: 0

      The Prime Directive forbids any interference in the convenient death of nonstrategic villagers, of course.

    2. Re:divert tsunamis from strategic buildings by LordLimecat · · Score: 1

      Who is that even supposed to be a criticism of, and why is it insightful?

    3. Re:divert tsunamis from strategic buildings by flyingfsck · · Score: 1

      Yup, we need to focus all tsunamis on Somalia. That will stop piracy and put an end to starvation in Somalia - since there won't be anybody there after a while.

      --
      Excuse me, but please get off my Pennisetum Clandestinum, eh!
    4. Re:divert tsunamis from strategic buildings by ultranova · · Score: 2

      Or we could focus tsunamis - and all other waves - to a reservoir and let it drain back to sea through turbines. Or we could build concentrated tidal power plants. Or whatever.

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

    5. Re:divert tsunamis from strategic buildings by Monoman · · Score: 1

      No no no that would never happen. I'm sure the plan would be to redirect it to circle on itself so it gets dizzy and falls down ... or form a giant vortex that sucks the entire earth into another dimension.

      --
      Keep the Classic Slashdot.
    6. Re:divert tsunamis from strategic buildings by Anonymous Coward · · Score: 0

      It should be obvious, "strategic" in this context means "important," which probably will translate to government buildings and rich people's houses.

    7. Re:divert tsunamis from strategic buildings by HiThere · · Score: 1

      Since the focusing is frequency dependent, I don't think you could use the same structure to focus both tsunami and ordinary waves. Still, you may have the inspiration for a new form of wave driven generator.

      Tsunami's are infrequent enough that aiming them at a reservoir to power a generator would be rather inefficient. I doubt it could be cost effective. And since it's salt water, most other uses of the reservoir would be impratctical. It would be nice if you could just bend it 90 degrees, but I think that would requrie knowing where the site of initiation would be. Diverting it, without specifying exactly where to can be done without knowing the angle of incidence.

      --

      I think we've pushed this "anyone can grow up to be president" thing too far.
  6. Deflector shields by cold+fjord · · Score: 3, Interesting

    I don't think anyone ever expected that something akin to actual deflector shields for use on earth might be practical anytime soon, that they would always be the stuff of science fiction. At least this offers the possibility of actually making something like them with matter and not a theoretical energy shield requiring massive nuclear reactors.

    Very interesting stuff - Metamaterials

    --
    much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
  7. Scale smaller than the wavelength? by PPH · · Score: 2

    Yes. The size of the structures may be smaller then the wavelength of interest. But they must be assembled in an array of a size on the order of the wavefront you want to divert. So you can redirect a seismic wave away from a town with an array of holes. Each hole might be of manageable size. But the array would be on the order of the same size as the town. That's a lot of holes and a lot of property you are going to be perforating.

    --
    Have gnu, will travel.
    1. Re:Scale smaller than the wavelength? by cold+fjord · · Score: 2
      --
      much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
    2. Re:Scale smaller than the wavelength? by sandertje · · Score: 1

      I'm not sure whether I understand the principles correctly, but if you can conjure up something that deflects seismic waves, you wouldn't need to drill holes under the entire city. All you'd need is a ring of deflectors around the city large enough to deflect a decent earthquake. The city would then only be unprotected in the unlikely event the epicenter is directly beneath the city. Even if that is, for some reason, impossible, underground work is required in most cities on a regular basis anyway. One could drill the necessary holes when the sewers are upgraded, new utility lines are being laid etc. Sure, that would mean at least several decades before completion for most areas, but most nation-scale infrastructure projects take that much time anyway.

    3. Re:Scale smaller than the wavelength? by HiThere · · Score: 1

      It's a bit trickier than that. You need a precisely spaced grid of materials with a different density. Holes aren't necessary. This kind of thing up above grould has been done with grids of posts. But if you're using holes, you can't run a sewer in the same area. It ruins the "crystal" structure.

      --

      I think we've pushed this "anyone can grow up to be president" thing too far.
  8. Locations chosen to protect 'wealth creators' by Anonymous Coward · · Score: 0

    If the redirected waves inflict more harm on outlying neighborhoods, that would be justified in the sense that those neighborhoods primarily consist of members of the 47 percent of the population who don't pay taxes.

    +100 for each Bloomingdales
    +10 for Starbucks
    +5 for Panera Bread, Dunkin Donuts
    -10 for McDonald's or BK
    -20 for Walmart
    -50 for Kmart, check-cashing store, pawnshop
    etc

  9. Insane... Lets be at least slightly real here. by Anonymous Coward · · Score: 0

    For the cost of the materials infrastructure you'd need to bend a tidal wave around even a small building. Let alone a town.

    It would be cheaper to move the town to somewhere you're not going to get hit in the first place. Far far far cheaper.

    Now unless you have a spare load of cash numbering into the multi multi trillions laying around... This plan is an insane idea.

    Soundproofing tho. That might be something.

  10. Re:5 Minutes of Computer Time by jimmydevice · · Score: 2

    cold fjord, is that you?

  11. Re:5 Minutes of Computer Time by Anonymous Coward · · Score: 1

    Dear Slashdot,

    My name is Mike and I am serving the first week of a 10 year sentence in Federal Prison for severe SEC violations.

    I call BS Mikey. I've seen the news for the past several years; nobody goes to prison for stock market violations anymore. All the SEC does is oversee the bailouts.

  12. Re:5 Minutes of Computer Time by cold+fjord · · Score: 1, Insightful

    I suppose it's pointless asking you to grow up?

    --
    much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
  13. Re:5 Minutes of Computer Time by Anonymous Coward · · Score: 0

    cold fjord, is that you?

    Yeah. That was exactly my thought also. Its got copkisser shill written all over it.

  14. Re:5 Minutes of Computer Time by Anonymous Coward · · Score: 0

    That can't be Cold Fjord then, everyone calls him an NSA shill. You must be trying to throw people off your track. Dude, you have no self respect!

  15. Re:5 Minutes of Computer Time by Anonymous Coward · · Score: 0

    Now that's some funny shit...

  16. Better idea by Anonymous Coward · · Score: 1

    Deflect tsunamis away from towns with atomic blasts.

  17. Re:5 Minutes of Computer Time by Anonymous Coward · · Score: 0

    Skewl?

    five good
    three days
    As such,
    says, "
    seven times

  18. "Developed" = "Imagined" by wonkey_monkey · · Score: 1

    Metamaterials Developed To Bend Sound Waves, Deflect Tsunamis

    Is it really "developed" when it's not actually been made yet? It's a bit like saying "Nuclear bombs developed to send man into space" when talking about Project Orion.

    I don't think much of their "related" articles either:

    ASTEROID MINERS PREPARING FOR GOLD RUSH IN SPACE
    SATELLITE IMAGE SUGGESTS NORTH KOREA HAS RESTARTED NUCLEAR REACTOR
    DEPRESSION AFFECTS MEN AND WOMEN EQUALLY: STUDY
    PRESIDENT OBAMA TO NAME FURMAN AS CHIEF ECONOMIST
    ASPIRIN TIED TO LOWER RISK OF SKIN CANCER

    --
    systemd is Roko's Basilisk.
    1. Re:"Developed" = "Imagined" by nmr_andrew · · Score: 1

      Metamaterials Developed To Bend Sound Waves, Deflect Tsunamis

      Is it really "developed" when it's not actually been made yet?

      No, it's not, but making grandiose claims about what something could become in mere decades (just possibly, if everything falls perfectly into place) is how you try to get a bigger slice of the ever dwindling pie of research funding. You need to grossly oversell every result.

      For those unaware, due to congressional meddling, the NSF effectively now requires you to tell it what great societal or economic problem your research is going to solve in the grant application, i.e. before you even get preliminary data. I'm afraid that overselling of all research is going to balloon in the next few years, as if it hasn't already.

  19. Re:5 Minutes of Computer Time by Thanshin · · Score: 2

    And thusly began The Saga of Cold Fjord and Peter Pan.

  20. Sound proofing... by Electricity+Likes+Me · · Score: 3, Informative

    This is where the money in this idea lies. If you had an effective way to completely deaden low-end bass, then you'd dominate the market. Being able to build a whisper quiet nightclub or listening room would be incredible.

    I'm about to embark on some deadening and sound proofing in my basement theatre, and I'm now thinking I really need to look into the metamaterial research to see if it can offer anything there.

    1. Re:Sound proofing... by zAPPzAPP · · Score: 2

      Too bad a single setup of meta material typically only works for a very specific wavelength.
      So, it could be helpful with applications using a defined wavelength (for example soundproofing an array of many ultrasonic transcievers from each other to reduce interference), but it won't mask you from a wide array of sounds.

    2. Re:Sound proofing... by Anonymous Coward · · Score: 0

      This has it's advantages in the right applications though. Highly frequency dependent metamaterial structures can produce wildly different wave patterns which can be used to do things like Compressively Sample (https://en.wikipedia.org/wiki/Compressed_sensing) a scene.

  21. Re:Insane... Lets be at least slightly real here. by Thanshin · · Score: 1

    For the cost of the materials infrastructure you'd need to bend a tidal wave around even a small building. Let alone a town.

    It would be cheaper to move the town to somewhere you're not going to get hit in the first place. Far far far cheaper.

    Now unless you have a spare load of cash numbering into the multi multi trillions laying around... This plan is an insane idea.

    Soundproofing tho. That might be something.

    A - Cost of materials: ?
    B - Cost of moving a city: ?
    C - ? if far far far cheaper than ?

    Therefore: Insane idea. (unless you have multi multi trillions.)

  22. Even Better idea by Thanshin · · Score: 2

    Deflect towns away from tsunamis with atomic blasts.

  23. We've been there and done that by Anonymous Coward · · Score: 0

    Deflecting wave energy from your property is no better than some asshole dynamiting a levy on the opposite side of a flooding Mississippi to protect his own home at the expense of a neighbor.

    That has actually happened.

  24. Metamaterials show roperties not found in nature? by Anonymous Coward · · Score: 0

    > Metamaterials are simply materials that exhibit properties not found in nature, such as the way they absorb or reflect light.

    How's this not a metamaterial? And it's natural!

    There are many metamaterials around. Just look carefully.

  25. "Metamaterial" the new "Nanotechnology"? by Anonymous Coward · · Score: 0

    It seems to me that "Metamaterial" is the new "Nanotechnology".

    A few years back Nanotechnology was that new kind of technology on the scientifiy fridge no one really new about but the promises were endless. That were the 2000s.
    Before it was Gentechnology (the 90s), before that it was "Cyber" (80s). We can go back to the 50s where it was neclear technology that was supposed to save mankind and I am pretty sure in ancient Rome there was someone who once said "Just wait until the new slaves from arrive, they're all magic and do all kinds of wondrous things!"

    It goes like this: New technology is found, scientists research. After a few years it then sinks down into popular sciences and more research team pick things up, then the speculation on sites like this starts about all kinds of wondrous things. Then things calm down, the first applications of the technology show up (or not) and also some bad side effects are found. More applications show up and somehow the world is not fundametally changed.This is followed by the next Hot Thing of the Decade. Expect a lot more "Metamaterials" articles during the 2010s, folks. In the 2020s we'll then read about Hyperfibers (or whatever) which were recently found but are like 20 years from practical (and cool but not *that* magic) applications.

  26. Tsunami "Bending" happens by dbIII · · Score: 2

    Coastlines do it. Features on the ground do it. Stop thinking in terms of energy versus energy because that's not what is being suggested. It's not about matadors headbutting bulls but instead getting them to move in a path at an angle that won't hit them.

    1. Re:Tsunami "Bending" happens by Anonymous Coward · · Score: 0

      Yes, it is not a question of energy -- it is a question of wavelength. The wavelength is so big, we're talking 10s of km, even close to the shore, that building man-made structures to bend them is somewhat insane. A seawall, for all its limitations, is somewhat thinner (and less expensive!) than that.

    2. Re:Tsunami "Bending" happens by dbIII · · Score: 1

      You are confusing the length of the wave front with the wavelength. Try swinging what you've got in your head around ninety degrees to cut through the wave cross section and you'll see that the scale is far more manageable.

    3. Re:Tsunami "Bending" happens by fatphil · · Score: 1

      The greatest amount of damage from tsunamis happens when *other things* bend the tsunami. Anything which diverts the energy away from one thing diverts it towards another thing. Heaven help you if you've got two things diverting the energy towards you, such as sides of a bay, as then you're more likely to have an e^-kd rather than k.d^-2 reduction in energy (an extreme - compare losses in fibre optics to the inverse square law).

      --
      Also FatPhil on SoylentNews, id 863
    4. Re:Tsunami "Bending" happens by Anonymous Coward · · Score: 2, Interesting

      You are confusing the length of the wave front with the wavelength. Try swinging what you've got in your head around ninety degrees to cut through the wave cross section and you'll see that the scale is far more manageable.

      Am I? I don't see how that is... and I'm a tsunami researcher! Literally, I've spent years of my life running (and developing the models for) tsunami simulations.

      Earthquakes typically happen on scales of O(100km), so the initial waves produced, often at depths around 4km, have a wavelength of O(100km). In shallower water, say 100m, the wavelength is then O(10km), as the wavelength goes with the square root of the depth. There are other tsunami sources too, but we'll just stick to an order of magnitude estimate.

      Now you see how metamaterials, which are structures with many sub-wavelength elements gathered in a way to produce interesting macroscopic behavior, would be difficult to use for tsunamis. You want to create structures in the ocean that are maybe O(10km) into the ocean, and then probably also O(10km), maybe more, along the shoreline to protect a city? And you'll need them to be substantial in the vertical, as well, since this isn't like laying down a tarp.

      The comment in TFA about deflecting tsunamis was just an offhand thing, by someone who specializes in a completely different thing... I wouldn't put any weight in it. Even if you found a way for something to actually work, and somehow have a price tag that is not astronomical (you have any idea how much it costs to move even "dirt" around offshore?), I can't imagine anyone building it -- the seafloor is remarkably well utilized off most big cities, between cables being run out, channels for shipping, fishermen needing certain places undisturbed, offshore dumping locations, etc.

    5. Re:Tsunami "Bending" happens by drinkypoo · · Score: 1

      Sure, but if everyone could divert the Tsunamis back into the open ocean, they'd dissipate eventually.

      A bigger problem is that their large-scale test involved changing the composition of an entire area between source and sensor. So are we supposed to build umpty-zillion pillars in the ocean or something? Probably infeasible.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    6. Re:Tsunami "Bending" happens by dbIII · · Score: 1

      I find that very hard to believe that the wavelength would be so long in shallow water. Don't they come in as multiple waves that can be seen from the shore at once? How can that be so with a wavelength of 10km?
      Also, for on land, I seem to remember from geophysists that ground roll does not have the sort of wavelength you are speaking of and that's a major cause of damage in earthquakes.

    7. Re:Tsunami "Bending" happens by Anonymous Coward · · Score: 0

      I find that very hard to believe that the wavelength would be so long in shallow water.

      "If it's truth you're looking for, Dr. Tyree's philosophy class is right down the hall."

      Don't they come in as multiple waves that can be seen from the shore at once? How can that be so with a wavelength of 10km?

      Sometimes. Depends on the tsunami, and depends on the profile of the beach. The waveform is quite complex. There is often quite a long tail, but most of the damage (except in some harbors or islands) comes from the first few wave periods. This period may be 10-20 minutes, let's say. If you look from the coast, if you happen to have a shallow beach profile (the process does not happen with a steep beach profile), as the wave approaches the shore, you would not see these individual waves -- but you would see multiple wavefronts, and the crests of these are not 10km apart, but maybe a few hundred meters apart. What you'd be seeing is an undular bore, produced by a single wave from the nonlinear and dispersive terms in the wave equation. Many times even the crests of this bore are breaking. These crests are sort of "riding" on the larger wave.

    8. Re:Tsunami "Bending" happens by dbIII · · Score: 1

      Thanks. I initially wasn't sure if you'd thrown out an off the cuff "that can't be right" or had actually put in the thought you now appear to have put in.

  27. Energy level doesn't matter in this case. by Ungrounded+Lightning · · Score: 1

    You are talking about redirecting amounts of energy in a wall of water than may be 10-20 feet high or more, yet it comes in as a solid wave and the elevation stays at that height causing water to move inland extremely fast for a long time.

    It would be easy to calculate what amount of energy that would be in a width of a town: ...

    Yes, you are. So what? That energy is spread out over a very wide area. You're talking about building a "lens" over a similarly wide area - out where the "tsunami" is a gentle (though fast-moving) rise of a couple inches to a foot - representing a water current that's comparable to other wave action. The only thing special about a tsunami is that it's a very low frequency wave.

    A mirror, lens, or metamaterial doesn't care HOW much energy it's handling, until the energy density gets high enough to start damaging it. The energy density of a tsunami, spread out over those same several miles or whatever, is quite low.

    In fact, it's a similar structure acting on the wave - the gradual rise of the seabed as you approach the beach - that concentrates the energy of the tsunami, along its direction of propagation, into a destructive, abrupt, wavefront.

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
    1. Re:Energy level doesn't matter in this case. by Anonymous Coward · · Score: 0

      A mirror, lens, or metamaterial doesn't care HOW much energy it's handling, until the energy density gets high enough to start damaging it. The energy density of a tsunami, spread out over those same several miles or whatever, is quite low.

      Water waves are substantially more nonlinear than optics in ordinary situations. This thread is hysterical... bunch of people commenting on physics that they don't understand at all. Next up, let's see what Britney Spears has to say about which 3D printer is best.

      http://xkcd.com/793/

  28. Build a great harbor without a seawall! by Ungrounded+Lightning · · Score: 2

    divert tsunamis from strategic buildings and towards some poor fishing village full of primitive natives nobody cares about.

    How about building a great harbor and calm beach without a seawall, bracketed by two regions where the surfing is GREAT!

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  29. Or send it back out to sea. by Ungrounded+Lightning · · Score: 1

    divert tsunamis from strategic buildings and towards some poor fishing village full of primitive natives nobody cares about.

    You can also use this to send the wave back out to sea - and defocus it while you're at it, so it's just a slightly higher wave than usual when it finally gets to another piece of land.

    This is what happens to it when it hits shore: Some of it bounces and is diffused - or possibly focussed. By doing this intelligently we can make it SMALLER when it hits the "secon

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
    1. Re:Or send it back out to sea. by Anonymous Coward · · Score: 0

      There were places off Japan that saw 40m of runup... you propose that we build a 40m wall, like a fence, around the coastline of every city? Of a whole country, perhaps?

      Wait a minute... you don't live in Texas by any chance, do you?

  30. So put it under a freeway! by Ungrounded+Lightning · · Score: 3, Interesting

    Each hole might be of manageable size. But the array would be on the order of the same size as the town. That's a lot of holes and a lot of property you are going to be perforating.

    It must be on the scale of the town IN ONE DIMENSION. Linear-square law: The bigger the area you're protecting, the lower the percentage of the area you need to perforate.

    So you need to perforate a strip around the town to do this? Do it while you're ALREADY perforating such a strip. Like when you're building (or revamping) the next beltway-freeway around the city of interest, or approving a rezoning for the construction of a new outer subdivision.

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  31. Breakwater design by flyingfsck · · Score: 2

    Breakwater design has changed a lot over the centuries. The primary design will deflect the waves using a heavy earth and rock embankment. Over time, it was found that an embankment made from irregular rocks or concrete castings work better than regular cubes. You could call that a meta material if you want, but it is simply a smart way to combine deflection and interference with the waves to achieve the desired smoothing effect.

    --
    Excuse me, but please get off my Pennisetum Clandestinum, eh!
    1. Re:Breakwater design by Anonymous Coward · · Score: 0

      6-foot concrete caltrops. The first metamaterial.

  32. Just gaming the system by Anonymous Coward · · Score: 0

    He is collecting moderation points here. Expect some NSA/Wikileaks story soon where he and his buddies can use the points to direct the conversation.

    1. Re:Just gaming the system by Anonymous Coward · · Score: 0

      If he really was NSA he wouldn't need to do that, he'd just hack the moderation system. I'm calling BS.

  33. Finally by ketomax · · Score: 1

    We finally discovered Wakanda!

  34. Metawords by bug1 · · Score: 1

    Someone should invent metawords to defelect metawords.

  35. This is new?? by Anonymous Coward · · Score: 0

    Hasn't this been known about for a VERY long time?

    There was a sea platform that had a metamaterial platform design around its base to direct waves around it.
    It was so far back I can't even remember the year now.

    Sound and vibrational energy are new here admittedly, don't remember anything on those, but I haven't even checked in-depth so there could be.

  36. Metamaterial lens has ten times more power by cold+fjord · · Score: 1
    --
    much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
  37. Hard to be a metamaterial with that definition by Anonymous Coward · · Score: 0

    If a metamaterial is defined a material that exhibits properties not found in nature, once it is created, wouldn't it stop being a metamaterial as soon as one is created? After all artificial materials is a proper subset of natural materials.

  38. Bend it like Beckman by Anonymous Coward · · Score: 0

    Bend it like Beckman and route it to your enemy's goal

  39. Re:5 Minutes of Computer Time by Anonymous Coward · · Score: 0

    that's alright. you're screaming into a void right now as it is. another layer of emptiness would be redundant.

    long live the cake overlords.

  40. inertia by l3v1 · · Score: 1

    I'm not a physicist, but I'm pretty sure these materials can't 'bend' inertia and mass, making this talk about diverting tsunami waves sound pure nonsense.

    --
    I am putting myself to the fullest possible use, which is all I can think that any conscious entity can ever hope to do.
    1. Re:inertia by Anonymous Coward · · Score: 0

      Electromagnetism is a type of wave in space. A tsunami is a type of wave in water. Seismic activity is a type of wave in earth.

      The same type of mathematics is used to describe them all: waves through a medium.

      Metamaterials allows us to modify the medium waves travel through in precise ways to control the propagation of the wave. Therefore metamaterial techniques are available in all of these situations.

    2. Re:inertia by Anonymous Coward · · Score: 0

      Electromagnetic waves carry momentum, yet they are bent by a lens. If you measure very carefully, you can even observe a change in the momentum of the lens as a result.

  41. Lex Luthor could use this by MemoryAid · · Score: 1
    Imagine if Lex Luthor controlled a construction company that did major projects around the Los Angeles area. With each project carefully selected by location, he builds, over the years, a lens that will focus earthquake energy onto a specific building to be specified later, perhaps with a tie-in to current events, destroying it completely.

    I should note that I haven't really kept up with Lex Luthor's aspirations since the 1978 film.

    If he could come up with a good way to trigger the earthquake, the film could be a remake of Black Sunday. Or at least use a similar target.

    --
    Language students: Don't try to learn English here. This ain't it.
  42. Re:5 Minutes of Computer Time by Anonymous Coward · · Score: 0

    That can't be Cold Fjord then, everyone calls him an NSA shill. You must be trying to throw people off your track. Dude, you have no self respect!

    That's so sweet, CF. You actually believe there's a difference.

  43. Re:5 Minutes of Computer Time by cold+fjord · · Score: 1

    ..... and once the trolls had gone to live with the fairies, and the griefers to live with the pirates, the spell was broken so they could never trouble anyone again. And everyone else lived happily ever after. The end.

    --
    much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
  44. Re:5 Minutes of Computer Time by Anonymous Coward · · Score: 0

    You should get some ointment for your butt hurt.

  45. a good prototype might be by Anonymous Coward · · Score: 0

    constructing a rapmobile that directs the emanating noise to the crotches of the occupants

  46. Re:5 Minutes of Computer Time by Anonymous Coward · · Score: 0

    You should get some ointment for your butt hurt.

    Sounds like one of your many closeted gay allusions. Let it go. Just ask. Someone will be more than happy to help you fulfill your prison fantasies.

  47. Re:5 Minutes of Computer Time by RockDoctor · · Score: 1

    But now, thanks to metamaterials, we don't have to listen to your screams.

    FTFY

    Just because we don't have to listen to his screams doesn't make it any the less fun.

    --
    Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"