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Old 11-21-2012, 04:18 AM   #1
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Sound

Okay, I'm probably not going to explain myself very well, but I'm going to try, and whoever can understand what I'm trying to ask gets 10000 internet points.

Say you hit a tuning fork and recorded the sound. If you had whatever equipment you required, could you determine, from that one sound, where the sound originated on earth. I'm wondering, if you had the means to examine the sound at it's most minute details, would it be unique to one spot on earth?

Would atmospheric pressure, altitude, density, pollution (or any other variable). . . etc etc influence pitch (even if not detected without the most sensitive equipment?)
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Gha - I'm going to regret posting this, aren't I? I'm going to reveal myself to be a real science idiot :\

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Old 11-21-2012, 04:29 AM   #2
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Sound is a movement of pressure through a medium in a wave-like form. Pretty much, sounds is like the radiating waves in water.

Density and pressure can affect sound. Sound can be recorded from water, but it's much harder for the wave to travel because of the density of water, and the pressure added to it.

By the best of my knowledge, no part of our atmosphere can affect simple pitch. If you recorded the tuning fork in Death Valley, or out of an airplane; I wouldn't think there is any difference.


Why are you asking? If you're locating a sound's origination, or orientation, I'd focus more on the reverberation and echo, fed back through the microphone. (echolocation).
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Old 11-21-2012, 04:50 AM   #3
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Thanks for taking the time to try to understand me, Will! Much appreciated!

Basically I want there to be a way that you could use a pitch or a vibration to locate any spot on earth (as if there exists a natural vibration that differs even by a few meters). Does, for example, there exist a natural background vibration given off by earth, or some force (gravity, EM, seismic...), that might be unique to a very specific location?

Maybe there's some theory out there that makes such speculations, or perhaps it's possible but requires a city-sized piece of machinery to pull it of.
do lot triumph tphcm ao chip do dung cho be vay cong so chan vay cong so nu chup anh cho be o ha noi
Something that could be as accurate as GPS.
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Old 11-21-2012, 05:05 AM   #4
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No, not with anything approaching current technology and science. Perhaps in a thousand years or so, but even then it's doubtful.

The only way to use a recording like that to find a location is from the background noise, if there are birds, what's the range of those birds, is there urban noise, that might help etc.

None of that is as accurate as GPS (unless the background noise is hyper-specific), nor could it ever be.
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Old 11-21-2012, 05:20 AM   #5
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Tech that won't exist for a thousand years, is something I can work with. But I'd prefer if there was some theory that existed that would support the hypothesis.

Maybe if I explain my thought process a bit. though I might further reveal my ignorance ....

I was thinking about gravity and how technically our weight changes based on our distance from the earth's core (i.e. you weigh less on a plane than you would at the Dead Sea). So, if it were possible to have all the information to the smallest integer, you could potentially ascertain location based on weight - must be exactly x distance from the core, and there is only one place on earth that fits that exact distance. So I started wondering if there were something a bit different. i.e. perhaps there are seismic tremors that exist constantly and perhaps the vibration of those tremors would have a minute variation that would be unique to a specific location on earth (given the different material those vibrations pass though en-route to the surface. (even if that variation is indistinguishable by today's equipment).
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ETA: I didn't make the connection to the tuning fork in my first question, but what I wondered was, hey, what if tapping a tuning fork in location "x", was influenced by surrounding . . . something (gravity, distance to sun, distance from core, a combination of things . . . I'm not entirely sure, but something...) that it would be slightly different than tapping that same tuning fork in location "y."
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Old 11-21-2012, 05:38 AM   #6
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The closest thing I can think of is doing sonar imaging to visualize the location by shooting sound waves at nearby geographical features. But that would require a great deal of data to get usable results.

The stuff about weight and earth's core is...uh, not likely. I have to ask, if in your story someone theoretically has access to data about seismic tremors, why don't they also have access to sophisticated visual data that would make it MUCH easier to locate this position? Why does it need to be sound?
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Old 11-21-2012, 05:44 AM   #7
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The closest thing I can think of is doing sonar imaging to visualize the location by shooting sound waves at nearby geographical features. But that would require a great deal of data to get usable results.

The stuff about weight and earth's core is...uh, not likely. I have to ask, if in your story someone theoretically has access to data about seismic tremors, why don't they also have access to sophisticated visual data that would make it MUCH easier to locate this position? Why does it need to be sound?
I'm in the planning stages right now . . . clearly And the story might not go anywhere. But it's not about having access to the data, it's about having a device that, when triggered by a specific vibration links to a location on the globe where that same vibration occurs naturally. But if there are no such naturally occurring vibrations that would differ slightly from one location to another (i.e. one step to the right), I might be at an impasse :/ do lot triumph chinh hang do lot nu hang hieu do so sinh khac vest cong so nu ao so mi nu album anh be dep
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Old 11-21-2012, 06:28 AM   #8
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I'm going to say that there's no such thing based on years of recording audio and fiddling around with it as a DJ and my general science background.

Seagulls in Maine sound the same as seagulls in Seattle so you can get a general idea from their noisy squawks that the recording was made on the coast but it doesn't point you to Coos Bay, Oregon or to Zijuatanejo, Mexico - it's just coastal sounds.

The sonic fingerprint of a room would let you get a general idea if you were in a similar room as to where the recording was made but not a specific room. I can record a singer in a cathedral but you couldn't tell which cathedral it was based on the playback of that recording. You'd need a ton of other noises that give you the clues needed to find that place and they have to be sounds unique to a particular area. Even then, without outside knowledge that these sounds only show up in one spot you aren't going to get the information you need.

In mystery stories you'll have people hear background noises that help them narrow down where the victim is located. The assumption is that the sleuth knows the whole town and can tell you based on bird noises and the presence of traffic and kids laughing and other nature sounds that the phone call came from a park. Which park? Why Plot Point Park of course! In a big city with lots of parks that still doesn't narrow it down until you get another noise specific to a park like the low rumble of a train passing. Aha! Your sleuth remembers that only one outdoor park also has a rail line passing nearby.

All of that outside information is what guides them to that park, not the specific sounds themselves.

For an alternate technology that could give you much more specific information about a location check out this video on femto-second cameras:
http://www.youtube.com/watch?v=JWDocXPy-iQ
http://www.bbc.co.uk/news/technology-11544037

The technique isn't very refined yet but it shows promise.
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Old 11-21-2012, 11:10 AM   #9
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There are some places with naturally-occuring vibrations, OP - near waterfalls, for instance - but there is no all-pervading set of vibrations that can pinpoint a location on the planet just by existing (or if there is, we can't detect it). The other posters who say we determine these things by background noise are correct, and a lot of people don't realise just how much you can pick out of background noise. Ambient sound can tell you a lot (or nothing at all, if there isn't any).

Even if you had an earthquake at just the right moment, you'd still get a selection of possible places rather than the right place, due to how waves propagate.

From your original thought, gravity gets stronger and weaker, but (as far as I'm aware) it doesn't change in anything else but magnitude. You can't sample it and say 'I'm here!', you can only sample it and say 'I'm this high!'

Now, what would be the reason on a planet where you could do that? A living planet would be really interesting, or the old stop-gap alien tech, or even a mantle that has solid bits suspended in it that make specific vibrations and you can tell where you are by their interaction as a sort of reverse-GPS...

Or you could just pick up a GPS signal or other triangulation signal, like a cellphone's connections...
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Old 11-21-2012, 12:10 PM   #10
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I want to emphasize what WillSauger was getting at: pitch is just the cycles per second at which something vibrates. Pitch will not be affected at all by atmospheric conditions. Let's say you struck a tuning fork in the vacuum of space. You won't hear anything (because there's no medium for the vibration to travel through), but the pitch of the tuning fork will still be 440 cycles per second (if it's tuned to middle-A, which most of them are).

Timbre, on the other hand, is basically what the note sounds like. A tuning fork, a piano, and a clarinet can all produce a pitch of 440 hz. They can all play the same note, but the timbre of the pitch will be radically different due to the size and shape of the instrument, what it's made out of, how forcefully the note is struck -- and, of course, where it is struck.

Theoretically, the answer to your question is yes (as long as your theoretical technology is analyzing timbre not pitch). If you had, say, a database with information on the physical makeup of every square foot of planet earth, then you could analyze a sound and cross reference that to match up with a specific location. You'd have to have a lot of data (right down to where a particular house pet was sitting at a particular point in time), but yeah, I think it could be done.

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Old 11-21-2012, 12:22 PM   #11
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I call bullshit. You'd need an entirely impractical database of how every place on the entire planet sounds, and you'd be assuming that nothing ever changes. Except it does. Everything is changing constantly, in balance with each other.

You write something like that, and I for one am out on the first floor.
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Old 11-21-2012, 04:46 PM   #12
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I can make the story idea work without the sound, but I kind of want it b/c I have an idea for a piece of technology to explain a historical event that would be very 'twisty' to the plot.
do lot triumph do lot nu goi cam bao tay cho be thoi trang cong so nu ao so mi cong so album anh cuoi dep
Soooooo, if I dare to try again . . . doesn't every single thing give off vibrations? If, at it's core, we're talking about atoms, or electrons, or whatever is smaller than electrons . . . moving at varying speeds, bouncing off each other, wouldn't that cause vibrations? And since no two things would be made up of exactly the same number of atoms, wouldn't the vibrations vary by every fraction of a mm across the planet?
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Old 11-21-2012, 05:03 PM   #13
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Sorry, Profen. Every single thing is comprised of atoms that give off vibrations - but as I understand quantum theory, those vibrations are not static. As something gets warmer it gains energy and the vibrations increase; as something cools it loses energy and the vibrations decrease. And, even worse, the very act of listening to something's vibrations would affect the vibrations of the thing being listened to - not to mention what the microphone's own vibrations would do.

This is before we start talking about the surrounding objects not being permanent parts of the earth itself - I mean, you might conceivably end up fairly sure that that's a particular coin you're hearing, but where exactly *is* it?

It'd be easier by far to have another excuse - in archeology, the region in which someone grew up can be identified by the isotopes in their teeth, for instance, and these days things that can be used as trackers are in widespread use by ordinary people.
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Old 11-21-2012, 05:08 PM   #14
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Thanks Clare - and thanks everyone for bearing with me here. I shall think on this some more . . . quan ao thoi trang dep ao chip do so sinh loai khac cho be thoi trang cong so nu thoi trang cong so nu trang phuc cuoi
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Old 11-21-2012, 05:28 PM   #15
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Okay I've thought about it for a whole 20 minutes. Let me try something else.

What if you had a means of measuring a single particle, and not just measuring it, but tagging it, the way you tag a fish? What if you could record the GPS location (ETA: it's location, +/- a meter . . . not it's precise location) of that tagged particle? What would be unique about that particular particle that could be monitored? It's vibration? Would that tagged particle still be in approximately the same place in a day, a week, a month . . . do particles cease to exist? quan ao thoi trang han quoc ao lot nu do so sinh khac thoi trang cong so gia re thoi trang cong so gia re trang phuc co dien
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Old 11-21-2012, 08:01 PM   #16
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PS - I appreciate you indulging me, guys. I am sure you feel how doctors must feel when a patient brings in their own "research" to explain a condition :/ quan ao thoi trang do lot nu hang hieu bao tay cho be thoi trang cong so thoi trang cong so trang phuc co trang
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Old 11-21-2012, 08:10 PM   #17
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Okay I've thought about it for a whole 20 minutes. Let me try something else.

What if you had a means of measuring a single particle, and not just measuring it, but tagging it, the way you tag a fish? What if you could record the GPS location (ETA: it's location, +/- a meter . . . not it's precise location) of that tagged particle? What would be unique about that particular particle that could be monitored? It's vibration? Would that tagged particle still be in approximately the same place in a day, a week, a month . . . do particles cease to exist?
This is a far more complex question than you might imagine. Each particle that exists has a certain set of quantum numbers that effectively define what it kind of particle it is (I'm being a bit sloppy here). To tag the particle you would in effect have to add a characteristic to something that has only a limited set of possible characteristics. So what could act as such a tag? In Quantum Mechanical terms there isn't anything.

Particles do indeed cease to exist, either by decaying into other particles or by interacting with other particles to produce yet more particles.

An example of decay happens with neutrons. A neutron can decay into three particles: a proton, an electron and a kind of neutrino called an electron anti-neutrino.

An example of combining is the opposite process to the above: proton + electron + electron anti-neutrino = neutron.

Furthermore, certain kinds of particles (called exchange particles http://hyperphysics.phy-astr.gsu.edu...les/expar.html) are emitted and absorbed whenever two objects are drawn together or pushed apart by a force. Each of the four forces has a corresponding exchange particle (for example, the electromagnetic force uses photons as exchange particles).

Photons are emitted and absorbed by atoms all the time. A photon of appropriate frequency can be absorbed by an electron in a particular energy state around an nucleus in order to jump it up to a higher energy state. The electron can then fall back down to a lower state and emit another photon.
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Old 11-22-2012, 08:42 AM   #18
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Audio mechanics and quantum mechanics aren't going to give you the 'locator' device you need. Why not clue us into what it is you're trying to achieve? Locate someone in time and space - THROUGH time and space? A person. An object?
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Old 11-22-2012, 03:24 PM   #19
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Originally Posted by profen4 View Post
I was thinking about gravity and how technically our weight changes based on our distance from the earth's core (i.e. you weigh less on a plane than you would at the Dead Sea). So, if it were possible to have all the information to the smallest integer, you could potentially ascertain location based on weight - must be exactly x distance from the core, and there is only one place on earth that fits that exact distance.
It would be a funny shaped world in which we'd live Seriously, this is impossible for a 3-dimensional object (or a 2-D one for that matter).
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...What if you had a means of measuring a single particle...
You need to be specific about what you mean by particle. A particle of what...dust, a sub-atomic one, etc.

Why don't you try magnetism?
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Old 11-22-2012, 07:41 PM   #20
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Why don't you try magnetism?
Is there something unique to the location at which a reading of magnetism or electromagnetism is taken? i.e. is the wavelength and frequency of electromagnetism variable from point "x" to point "y" if the two points are very near each other? do boi tre em cao cap do lot nu goi cam bao chan cho be ban si quan ao ban buon quan ao cac loai trang phuc bieu dien
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Old 11-22-2012, 10:24 PM   #21
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Is there something unique to the location at which a reading of magnetism or electromagnetism is taken? i.e. is the wavelength and frequency of electromagnetism variable from point "x" to point "y" if the two points are very near each other?
No, but the angle of dip (the direction of the magnetic north pole to the horizontal) varies with latitude. If you then transpose this on to a system which relates to true north (position of the sun or stars?), it should be possible to get an exact location. That's how homing pigeons are supposed to home in (I think!).
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Old 11-22-2012, 10:44 PM   #22
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Except magnetic North doesn't quite point up to true North. That's why you have to have maps that register declination - how far off your magnetic reading is from the geographic North. Then there are spots on the Earth where you have a sizeable magnetic field that wangs your needle all over the place and you don't point anywhere remotely North.

I think we're going round and round here because there is a fundamental misunderstanding of just how hard it is to place yourself at an exact spot somewhere on the planet.

You've got magnetic solutions that at least tell you where you are in a rough North-South line. You've got visual solutions that help tell you a lot about your teen-tiny local spot on the globe but unless you are in extreme conditions you can't resolve much more than your hemisphere or maybe quadrant on the globe. The big problem is taking a single measurement and then saying AHA here I am. You need something to reference against, some giant grid of points spanning the globe that allows you to say that you're X feet away from one of the known grid points. That's how GPS works, it has multiple signals coming down from satellites at a known orbit and angle away from you. You can then do some trigonometry and stopwatch calculations to figure out that the beep originated at this angle and height from satellite A and that gives you a line into space from your current spot. You then do that for another three satellites and then look at where those lines converge - it's where you're standing. Still you can't do this with one satellite signal, you need four of them for the GPS system to properly locate you. Radio location services typically use triangulation so you have to pick up signal from at least two towers to have enough data points to work from.

The world is big and the distinguishing features are usually a conglomeration of things, not one single metric. If you're talking sound then it's especially muddy - sound just isn't terribly practical for a location mechanism.
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Old 11-22-2012, 11:08 PM   #23
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Angle of magnetic dip can tell you where you are in latitude, but will tell you absolutely nothing when it comes to longitude. You can tell where you are north-south, but east-west you're still blind. By magnetic dip alone, you can tell you're on the equator - but in the Atlantic Ocean? The Pacific? Which desert is this? No idea.
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Old 11-22-2012, 11:49 PM   #24
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I obviously didn't explain it very well.

You use the magnetic sensor to locate the magnetic north pole and then a fixed vector system to determine the direction of the true north pole. The important thing to remember is that it is a dynamic and not a static system, so the differential could then (possibly) be used to determine a more exact location.

I'm not saying it is practical - just theoretically possible Of course, if anybody has got any other ideas....
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Old 11-23-2012, 01:03 AM   #25
profen4
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I might be in the process of coming up with another option . . . This is so not going to be asked well, but you guys have been great at indulging me, so I will give it a go.

If I had a small laser. Something like a powerful laser pointer. Is it possible for that laser to take a piece of what it's housed in and transport it to where the laser stops.

For example, if I shone a laser pointer at a wall would it be possible for a piece of the laser pointer to be torn free by the laser, carried along the beam, and embedded in the wall? I'm thinking a very small part of the laser pointer, i.e. a sub-atomic particle sized part of it that would come from the narrowed opening used to restrict the beam size.

I read that back and I think I might be the only one who will understand what I'm asking ... Ridicule me to your hearts content!
do boi tre em do lot nu sieu mong khan ta so sinh cho be ban buon ban buon trang phuc ca mua kich
*Thanks for the continued indulgence, folks.*
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Last edited by profen4; 05-14-2013 at 05:53 PM.
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