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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.'"
But now, thanks to metamaterials, we don't have to listen to your screams.
Have gnu, will travel.
and towards some poor fishing village full of primitive natives nobody cares about..
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
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.
cold fjord, is that you?
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
Because, as we all know, if you deal with a really large amount of energy, physics can't possibly work.
And thusly began The Saga of Cold Fjord and Peter Pan.
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.
Deflect towns away from tsunamis with atomic blasts.
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!
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[Fuck Beta]
o0t!
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.
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
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
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!
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