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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.'"
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.
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?
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.
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
Deflect tsunamis away from towns with atomic blasts.
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.
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.
There's nothing shameful on being old.
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.)
Deflect towns away from tsunamis with atomic blasts.
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.
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
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
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
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!
We finally discovered Wakanda!
Someone should invent metawords to defelect metawords.
A new way of seeing: Metamaterial lens has ten times more power
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
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.
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.
..... 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
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"