The Future of Sound: Part Two

that you have ever heard. I'm Jovin Strickland and I'm Joe McCormick, and today we're gonna dive right into part two of our two part episode on the future of sound, in which we discuss many that's certainly not all of the ways that scientists and engineers and techno geeks of all kinds are using sound to change the world of tomorrow. Right. So, previously on Forward Thinking, we talked about how sound works

and talked a lot about ultrasonic applications in medicine. So if you haven't heard that episode, I highly recommend you check that one out because we kind of lay the foundation for what we're gonna be talking about today. Right, So what are we going to be talking about, Well,

we're gonna pick up. I had said in the end of the last episode that our first story was going to be again about ultrasonic frequencies, but in a non medical application, and this is actually going to be about how UH Disney has partnered with Carnegie Mellon University to create UH controls physical controls for smartphones, and that you're they're using ultrasonic frequencies as the means for these controls to interact with the phone. Okay, so we're gonna have

to explain that a little better. You're you're not saying that you sing let it go at your phone to unlock it. No, if you could sing let it go at ultrasonic frequencies, I would be real impressed. Yeah. I've got a friend whose little daughter I think can do that, and then she should go on American bats have talent

and sing that out. That's fantastic. Well, now, in this case, the ultrasonic frequencies are being used in a similar way to what we've talked about before with the echolocation end of approach, where UH you measure you emit sound from one device like essentially a speaker transponder transmitter, yeah, and then you end up picking it up through another one receiver of some sort and by measuring the time it took for the sound travel from one and get back to the other, as well as any changes in the

frequency or wavelengths of that sound. You then can start to draw some conclusions. Well, in this case, Disney and Carnegie meil and have developed some hardware that could connect to a smartphone, and that hardware could allow you to control the smartphone in different ways. Usually the idea being that this is a proof of concept and that the apps will eventually allow you the different control schemes. So

we're talking about physical controls like a case. Imagine that you have a case that's essentially got a tube that runs around the perimeter of your phone. Now, one of the that tube is hooked up to the speaker of your phone, and one and the other end goes to the receiver. And then there's an ultrasonic frequency that's being emitted by your phone. So you cannot hear it. It is above the range of human hearing. But this can

be played just through a regular MP three. Yeah, yeah, I mean a phone can certainly play sounds that are well beyond the frequency of human hearing. For instance, every conversation I have with my wife, I can't hear half of what she says. Oh, so these frequencies, even though you can't hear them, your phone can admit them and detect them. Right, It's it's not limited by the same physical limitations we mirror mortals are subject to have human ears, right,

so it has tiny bad ears. Creepy if your phone had human ears attached to it. Though, well, yeah, you're right. I can't wait to see all the photoshop work that comes out of this anyway, So very Cronenberg. Okay, I'm sorry, Please go ahead. All right. So, so you've got this case and it's got essentially this tubing that allows the

sound to pass through. Now, if you were to have the the case sitting on a table and the phone, of course is in the case, it would be able to detect that because there's not any you know, there's no deformation of the case. You aren't holding it. If you are gripping it, it would deform the case just enough so that the receiver would detect that difference from the sound waves that are coming in. And in fact, the harder you grip it, the more it would change

that the nature of those sound waves. So you could create a physical control based on this, So you could end up creating a game that relies on this control system. So imagine that you've got a maze and then by gripping your phone with a certain strength, it makes the character in the maze turn in one direction, and by releasing the pressure, it makes it turn in a different direction. That's a simple example of how this could be used.

But they showed up tons of different ways of doing this, including methodologies that would have like a joystick or a valve control, or just a switch or toggle, things like pressure switches that would do things like allow you to change the volume on your phone or a lighting effect on your phone. Lots of different potential uses. Now, the

control system is just a platform, right. They haven't designed the apps around this, but they could do things like an alarm clock where you reach over and you squeeze part of the case around it and that's what tells it to go to sleep or turn off or whatever. Um. So what we're seeing now is the development of the hardware. The software is going to follow. I expect we'll see a lot of it because Disney is known for that kind of thing. But this kind of interesting that again,

they're using ultrasonic signals for this control system. It's not you know, using capacitors or electrical circuitry or anything like that is simply sound. Yeah, well, I mean, the the tricky thing in introducing anything electromagnetic into a system like a phone is that it has the capacity to interfere

with what the computer in the phone is doing. That's true. Yeah, yeah, I mean, you know, that's that's the truth with lots of different electrical components, is that, you know, electricity and magnetism have this relationship with each other, and obviously if your control system depends upon that, it could, depending upon the design, have the potential to impact other operations in a negative way or even just an unpredictable ways. This is using a control system based on sound that's not

going to interfere with other operations of the phone. So pretty interesting and also very different use of ultrasonic technology from what we were talking about before. So what if we were to talk about using ultrasonic frequencies not to create a control a physical control system, but a virtual control system, like virtual controls? Yeah, like like like there's no physical controls in front of you, but you can yet control electronic compos and it's based upon gestures and

it has nothing to do with camera technology. There are no cameras involved. It's only using ultrasonic frequencies. I like this idea because I'm creeped out by cameras watching me and this this would not be cameras watching you. This would just be essentially cameras listening to you. The the equivalent of sonar. Well really, really, it would just be sonar tracking your movements because again it's ultrasonic frequencies reflecting

off of surfaces. In this case you and the motions you make, and thus the motions you make can be converted into commands for a system. Lauren, this is your life in the future surveilled by a fish finder. So here's the other thing that they can do though, beyond being able to create a control system based upon your movements, it could even create haptic feedback. Now haptic feedback, this is a tactile feedback. Gamers have heard about this. Sure, sure,

that's a haptic feedback. Is like if you're if you've got a controller in your hand and there's a little librating pack in it that either maybe in a horror game, when your character is injured, you'll you'll feel the heartbeat through the through the controller, or if you're if you're shot in the first person shooter, you might feel the impact of that bullet like a thud. Yeah, Or you set the controller down on your wooden coffee table and then it vibrates and scares the heck out of everybody

in the house, mostly your dog. Yeah, I I I'm familiar with this, so yeah. The the idea being that every time you are able to engage another sense, when you want someone to experience some sort of virtual thing, whether it's a video game or a true virtual environment, any of those sort of things, you increase the level

of immersion. It adds a dimension to the experience. Yeah, yeah, I mean, and anyone who who uh you know, specializes in virtual environments will tell you that one of the things you want is to create this depth of experience. And the more senses you can engage, the deeper the experience seems. Um. You know, It's it's one thing to see stuff, it's another thing to see and hear. If you can see here and feel, then it adds another

layer of immersion. If you can see here and feel and smell with the y and then maybe you know, attach a couple of electrodes to your tongue so you can get the taste in there, and then you're really ready to go. But in your brain to take hold of your appropriate reception. So you can actually use ultrasonic frequencies to create haptic feedback. We've talked about how sound

has a physical force. It can it can press against stuff you're talking about, you know, moving air molecules, and if you do that with precision, you can create haptic feedback so that you can quote unquote feel objects that are not really there, they're just created from sound. We we've run right back into the creepy territory again. Okay, it could be creepy, but it could also be awesome.

So there's a British company called Ultra Haptics that's one of the groups that looking at bringing this technology to store shelves, and it uses ultrasonic frequencies to create acoustic radiation force, which are those little pressure waves, and you can create really precise ones. So they said that they could create something akin to a point that you would

feel with the tip of a finger. So they could create a pressure wave so precise that one fingertip would be enough to detect the full uh dimensions of that pressure wave, which is pretty incredible, right, that you could feel a physical point even though there's nothing there. Other than just the pressure waves created by sound, some kind of speakers hypothetically, Yeah, yeah, they have like a there's there's a speaker or an emitter. However you wanted to

find it. It would be it's it usually looks like a little like black panel, like a square panel that sits flat on a on a surface. That's what's generating these ultrasonic frequencies. Now, you could also do things that would stimulate, say the palm of your hand, so that you can feel when something is there. This would be great for like a Star Wars game where you're using

the force. I could totally imagine that being the feedback sort of stuff like I want to shoot lightning from my fingertips and you get a little pin pricky feeling. They're like, that's kind of cool, as long as it's not terribly painful. I mean, the dark side doesn't need to be, you know, truly dark at any rate. What is the feeling of force choking someone? It's so satisfying. Yeah,

clearly we've got two dark siders in this room already. Um. Although oddly enough, the lightsaber I used in that one episode was blue, so I'm clearly I'm using borrowing someone else's lightsaber for that episode of forward thinking. You could uh so you could create a like a virtual console. Imagine that you've got um, you know, you've got a

headset that's creating a virtual environment. You're you're looking around, and let's say you're on a spaceship and you've got a console in front of you, a virtual console that would control the spaceship's motions. You could use one of these emitters to generate pressure waves that when you put your actual hands out in front of you, so in the view of the virtual reality thing, you're your virtual

hands are in front of you. When you encounter the console, you would actually feel the feedback from that ultra haptic system, so it feel as if you had real controls underneath your hands. Now they might not be as refined as an actual physical control system, but you could feel something there, and by moving your hands the detection of those ultrasonic frequencies, or pairing this with a camera, you could end up

having that be translated into actual commands with the game. Cool. So, so you could you could have a you could feel a virtual panel under your fingers, and pressing a virtual button on the virtual panel would have an effect in the game. Yeah. Yeah, So, I mean I want to try this personally. I've never I've never encountered this technology myself, so I'm not sure exactly what it feels like or how hones of it is. But I mean Sonar is

certainly very responsible, responsible responsive, I mean you responsible technology. Yeah, oh boy. Well, in terms of game design, that is an interesting proposition because right now we typically have, you know, for most console based games and things, your your control hardware is very limited. H yeah. Yeah. You got the controller that you know you're going to be dealing with,

and you have to program around that. Sure, and even if you put ninety eight million buttons on there, which I think is where we're headed in forty years, right, But yeah, so what if every game designer could in the software design their own controller. I mean, that would be interesting and also be on the level of something like a connect where you could theoretically do that, but you're not going to have any feedback for the users.

So the users is putting his or her hands out in front of him or her and nothing has happened or stops happening in the game, but you don't feel it yourself, like there's no feedback apart from the actions that are playing out in front of you. All Right, you have to you have to kind of coordinate with the screen and managed to not feel entirely ridiculous as you're interacting with these things that certainly are not there

to you. I don't know if that's possible. Now, since we're already talking about eliciting some sort of emotional response, it's time to talk about how ultra haptics could really play with your emotions, at least according to the University of Sussex. Okay, so let's let's get this all the way first. I don't know how much uh to. I don't know how much I believe this next thing because it just seems so counterintuitive to me. But I am skeptical.

But I am willing to uh to consider it. Yeah, especially considering that the people who are researching this are

very much specialists in their field and I am not. However, University of Sussex used a system from ultra Haptics, that same British company we were just talking about, to test the ability to stimulate certain areas of a person's hand in order to elicit particular emotions, which seems which seems pretty you know, um crazy to me, like it's it's, it's it kind of reminds me of reflexology in a way.

But according to the actual study, uh, they had detected things like a blast of hot air on the area of your hand around your thumb, your index finger, and part of your inner palm could be associated with feeling excited, whereas a stimulation of the hand on the outer part of your palm and around your little finger could be associated with feeling sad. So potentially you could use this kind of system to end up affecting the emotional response

of someone operating with that particular system. So if you wanted to do something like tell a specific story, or you're playing, you know, a particular type of video game, and your goal is that you want the user to have a particular kind of emotional response, knowing that you can't truly control that, but you want to try and get the best potential to use everything you can. Yeah, and there's only so many blue tones and C minor keys that you that you can really fit into a

single game. So yeah, so if you could, if you could elicit sadness with this ultrasonic touch, then Honestly, every time I go on Xbox Live, I feel sadness. But it's mostly because I'm a bullet magnet. So that's I don't know. I get that's interesting, but I it kind of makes me sad to think about that. Being like like that you would supplement the quality of your storytelling with some kind of like a neurological trick, you know, when you think about maybe that's what maybe that's what

colors in art do? I mean I was about to say, I would. I would argue that a lot of the things that we're using are already psychological tricks, things like the music, you know, using a minor key instead of a major key, Like these are tricks that storytellers have been using ever since they've incorporated those sort of elements into their stories. So here comes the dark Knight of the Soul. Please lean over and allow us to touch

your tear ducks. Yeah I I do. I do actually get irritated whenever strings rise up in in a movie soundtrack in good days. So so maybe so maybe I would welcome this. Maybe this would be if it's not handled well, it definitely like you immediately pick up on it, like, oh, I see what you're trying to guess what, Mr Director, I'm not gonna feel sad just because that's what you want me to do. Do a teenager about it. I get that way too. I get very belligerent when I

when it's when it's like blatant. If it's worked in, well, then I appreciate it, you know, I appreciate the artistry. But if it's if it's like you know, no subtlety whatsoever, then I get belligerent, and any renuane emotions are so bored, you know. All right, fair enough, fair enough, Well, let's let's move away from emotions and ultrasound and ultrasonic frequencies. I've got a question. Almost everything we've talked about so far has been ultrasonic. Are there any technological uses we

can talk about for low frequency sound? Yes. In fact, there are some great examples of using lower frequencies to have physical effects. And one of them is something that really went viral a couple of weeks ago. You may have seen there was a video of a couple of students using a sonic fire extinguisher. They were yeah, so so it looks like they're they're holding this this thing that looks like partly a almost like a vacuum cleaner.

There's an enormous tube attached to it and they point it at a pan that's in flames, and the flames snuff out. And the device they're using generates low frequency sound waves, not ultra low. They are within the range of human hearing, around thirty to sixty hurts, so on the low end of human hearing. And what they knew that acoustic waves could affect flames. They being Seth Robertson

and Viet trend Tow students at George Mason University. They experiment with lots of different frequencies with flames because they knew that that these pressure waves could affect the flames themselves. We can can they affect the flames or can they affect the air that is fueling? Well, they affect the air that's feeling the flames, but that in turn affects the flames, so you know, you can sure we can

trace it back. Well. They found out that the ultrasonic frequencies that they first started with would make flames vibrate, but that's it, like the flames will get all all jiggy, but they wouldn't do anything else. So they're like, well, this isn't I mean, it's pretty, but it's not doing what we wanted to do, which is to have a safe chemical freeway of turning of extinguishing a fire rather

than making the fire cooler exactly so right, so groovy. Now, they then experimented with these these lower frequencies which generated pressure waves that would push essentially oxygen away from fuel. And if you know, you're triangle for what require what's required for fire, It's got three things, right, It's got fuel, heat, and an oxidizer. Generally speaking, we say oxygen, but there are other oxidizers as well. Uh So it needs those

three things in order for fire to happen. So the pressure waves push the oxygen from the fuel, thus the fire is extinguished. Uh So it's kind of cool. You watch the demonstration and they just point this thing at the fire. There's no visible you know, between the two. It's just the fire itself extinguishes. And very interesting, very potentially a huge um benefit to us. Like, imagine that your stovetop has one of these things installed above it.

So same as like the the vent that you're going to vent any smoke out of, you could have a system where if there was a kitchen fire on your stove, you could flip a switch or maybe even it's automatically activated, and when it detects a fire, it emits this this range of low frequency sounds and that ends up separating the oxygen from the fuel and thus the fire goes out, Yeah, without you having to scramble for a fire extinguisher spray

chemicals all over your food exactly. Yeah, so this could this could be a safe way of doing that and you don't have that those problems with the chemicals. It also could be very useful in say spacecraft, where if you're in a low gravity environment like a micro of the environment, and you also don't want blobs of chemicals floating all over the place, you probably don't want a chemical fire extinguisher. However, you also really don't want to

fire your spacecraft. As as bad as blobs of chemicals are, blobs of fire, a fire in micro gravity is is both terrifying and awesome to view. It really looks amazing. I don't know if you guys have ever seen fire, but it's it's it's spherical. Yeah, it doesn't elongate into the flame that we're used to it's a sphere. So yeah, just see a sphere of fire floating towards you. You'd want to put that out right quick. It's kind of like a little sun yeah yeah, plasma. Yeah, you want

to get rid of that. Uh sonic. A sonic fire extinguisher would be potentially a very good thing to have. Now, One thing that critics have pointed out, and this is important to remember, is that ultimately this fire extinguisher, what it's doing is severing one of those those three links. You know, you're severing the oxygen from the heat and the fuel. But hypothetically, once that oxygen is moved out of the way, the rest of the air is still

full of oxygen and it will move back in. Yeah, if you were to turn off the fire extinguisher so it was no longer pushing stuff out of the way, then once oxygen came back in, as long as the heat is above the ignition temperature of the fuel, it'll catch, it'll reignite. So what you would need to do is also end up lowering the temperature or removing the fuel, one of the two in order to make certain that it doesn't reignite. Once you turn off the fire extinguisher.

As long as it's still going, it should keep pushing the oxygen away. Uh. And the way they did this was they had an ultra or not ultrasonic, They had a sonic emitter H and an amplifier, and then they used a tube to focus the sound waves in the direction that they wanted because obviously otherwise we just radiate outward equally um and that's what was allowed them to

create these pressure waves that push the oxygen now the way. So, yeah, there's some limitations that would need to be addressed, or at least you would need to be educated on them in order to be able to use this safely to put out fires. That's really cool. And I want to talk about another use of acoustic pressure that is really fascinating and I actually didn't know about until recently. And this thing is acoustic levitation. So it is crazy talk time.

So is this when when music just floats through the air, and right, it's when when music elevates your soul and lifts you up into a higher plane of consciousness. Okay, all right, I got it. That's it. That's the technology. No, it's not. No, this is this is when you can use sound to manipulate objects in the air. So in a in a strong gravity environment like Earth's surface, this means you can actually use sound waves to levitate small pieces of matter to make it hover in the air.

Or in a microgravity environment, you could use these techniques to hold objects steady and keep them from floating around uncontrolled. So how on Earth does this work? How does it work? Joe? Well, have you ever seen the phenomenon of a standing wave in a fluid? I have not? You mentioned this before we started recording, And I mean maybe I have, but

I have no memory of it. I have, yes, But yeah, well, listeners, if you get a chance, you should go look this up on YouTube, just Google like standing waves in water or standing waves. It looks fascinating. So normally you have waves that propagate from one place to another, like if you throw a stone into a pond, the waves ripple out from the place where the stone landed. If you have if you have sound in a room, that's a

that's a compression wave, you know. But usually we'd we'd sort of represent it visually as a transverse wave of radiating out from the place the sound came from. A standing wave in a fluid seems to stand or bounce in place without traveling longitudinally, so instead of having crests and troughs that travel parallel to the motion of the wave. Again, technically sound waves don't have crests and troughs since they're they're not transverse waves. But this is just how we're

thinking of it visualizing. A standing wave has valleys of minimal pressure called nodes, and then peaks of intense pressure and those are called anti nodes. And it's these regions of differential pressure and standing waves that acoustic levitation makes use of. So scientists discovered, i think in the nineties seventies that if you aligned the standing waves just right, you could catch particles in the nodes and counteract the

force of gravity if you had the right kind of wave. Now, this is difficult to do because in the early methods of acoustic levitation, you had to have a speaker pointed at a reflective plate and it had to be just the right distance from the plate, you know, the resonant distance, and the speaker would generate a sound wave that was carefully calibrated for frequency and intensity in the distance so that when it reflected off the plate back towards the

source of the sound, the transducer that made the sound, It would cause an interference pattern in the sound waves

and that would create the standing wave. All right, So you've got the sounds coming from the speaker, the sounds being reflected back at the speaker, and those are the waves that are interfering and creating the standing wave you're talking about, right right, Okay, And so sometimes the transducers in these systems have had to be extremely powerful to create the level of sound intensity required to levitate objects against the force of gravity, probably depending on like how

heavy those objects were. Um Inner House stuff Works article on acoustic levitation our prind Tracy Wilson mentions that these transducers sometimes produced sounds exceeding hundred and fifty decibels d fifty decibles. Explain how how noisy that is? Well? I found a decibel chart used for an aviation noise comparison document created by the f a A. And according to this document, a noisy city street is usually about eighty

two hundred decibels. A power lawnmower or chainsaw is going to be a hundred or a hundred and ten decibels. A rock concert is maybe a hundred and fifteen to a hundred and twenty decibles, and a jet engine at close proximity is a hundred and thirty two a hundred and sixty decibles. Okay, so as loud as standing next to a jet engine. Yeah, so this is going to be loud. According to the same f a A document, it warns that ear pain can occur at a hundred

and thirty decibles. Ear drum rupture is common at a hundred and forty. So you wouldn't have wanted to have stood next to any of these early plate experiments. Well, acoustic levitation, the loud ones so REESA implementations seemed to be I it's it looked to me like they're focusing on ultrasound frequencies now which humans can't hear, thankfully, And that kind of makes you think you don't want your pets in the room while you're experimenting with acoustic levitation,

especially your dogs or bat. But do you have pet bats? I don't have pet bats. They are really cute. Well. More recently they've introduced features to acoustic levitation such as movement, so not just the levitation of objects, but two D and eventually three D spatial manipulation of a levitating object. So just recently a group of researchers in Japan created a system for three D manipulation that was a set of four phased arrays of speakers, sort of like creating

a box of sound. So here, instead of reflecting it off of a hard surface, they're they're producing sounds at all the sides. Yeah. And and by controlling with a computer very carefully each of these arrays in tandem, you can, uh, you can control that the pockets of canceled waves that can hold up an object. Yeah. So they the four walls sit in this square that's about to a side, and they produce ultrasound at about forty kill hurts, which is thankfully above where we can hear, about twice the

the upper range of frequencies that humans are capable of hearing. Yeah, And so what they do is they create this mobile focal point of levitation that's electronically controlled and it can move around within the square of sound. Yeah. They've been using this with really bitty little objects and light things. It looks like they've been using like styrofoam pellets and stuff like that a lot, uh, and and things that are only about a millimeter in diameter, but it's so

trippy and beautiful to watch. They can control entire like like swarms of these little pellets that kind of make them dance around. It's it's really really cool. And you might be thinking, a minute, couldn't we do this same thing with the electromagnets, you know, computer controlled electromagnets putting out thing. Well, in some cases you could, but acoustic levitation allows you to manipulate and levitate objects that are either non conductive so they don't respond to electromagnets, or

maybe electromagnetically sensitive. I thought so like if you you know, you want to handle something that's a that's that could be damaged by a strong electromagnetic field. Uh. And this is also sort of related to a concept that we talked about in the last episode, which would be acoustic tweezers using the acoustic pressure waves to manipulate small objects with with sort of a pushing or pulling force, all right, to to sort in our example, roaming cancer cells from

a blood sample. Yeah, but this has all kinds of potential applications in research and manufacturing, like the handling of extremely delicate or hazardous substances or components. They might be best done without touching the thing as if possible. They've also talked about using this in space you know where you where you want to control small things in zero gravity experiments. That makes sense. So, um, we're kind of

wrapping up some of the future uses of sound. We have some also some future research of sound we'll talk about. But to really kind of bring this all together, I wanted to talk about what's not not really that high tech use of sound, but is interesting. And it's funny because the stories I've read have presented this in such a way that sounds like you could use sound to

pay for stuff. In other words, you could use sound as a means of transmitting data to pay for something, but at a range that's beyond human hearing, so that you know you're not just shouting out your credit card number to everyone who can hear you. I was about to say, I I use sound to pay for stuff all the time. Yeah, but this would be more of an automated way of doing it. That would be akin to something like NFC. However, if you actually look into it,

it's a little less um dangerous than that. And I'll explain what I mean in a little bit. So we were specifically looking at this the story that talked about a means of transmitting information using high frequency you know, ultra high frequency sounds so that it's beyond the range of human hearing. Once again, and we're talking specifically about a system that has been implemented by vera phone using an app called way to Ride that it works with

New York City taxi cabs. Uh. There are a lot of those, like thirteen thousand in the city that have been outfitted with this particular system. Okay, that's not that many. Really. Yeah, in Atlanta, we've got four taxicabs at any rate. Um, here's how it works. So you've got a speaker in a taxicab that admits this ultrasonic frequency, so we can't hear it, but you turn on your your phone and you activate the way to Ride app, and your phone

can completely detect this ultrasonic frequency no problem. And that frequency is essentially associated with that cab. It's a unique frequency that that cab alone is is allowed to use. Uh. So your app would then send this frequency information over cellular data networks, so same way it would do any other kind of smartphone activity. It would go to the

servers for a way to ride. The servers would look up the database of all the different cabs and the different frequencies associated with each cab, find the one that specifically pertains to the frequency you sent, and then send back the payment information you had created in your profile

for that app. So when you install the app, you would create a user profile that would include your preferred payment methods for using this taxi service, and you could end up having an auto pay option, so that's all you have to do. It's kind of like what you might experience if you have Uber and you're using a digital wallet, or you could have one where you choose

which option you prefer at the time. So a lot of these, you know, these taxi cabs have monitors built into the back seats or the well about back of the front seats, i should say, and you could use that to choose your preferred method of payment at the moment when you need to pay for your cab, and do things like choose a tip and all that kind of stuff. So that implementation, I think makes a lot of sense because the only information being transmitted through sound

is the taxi cabs. I d that's it right, because if it were payment information, then you've got some potential problems, like if someone else is recording those sounds, just because you can't hear them doesn't mean recording device couldn't pick it up. If the if that particular frequency was associated permanently with your I D and your payment information, that clearly is a bad thing. You're talking about, you know, identity theft or are just fraudulent charges, that kind of stuff.

So you would want to make sure that any information that's being sent over sound waves is going to be non vital to that transaction, right, just an identifier for the for the cab or for the store or whatever it is. Right. So I mean that particular implementation makes a lot more sense to me because a lot of the information I was looking at there saying, oh, it's

like NFC not really. Near field communication uses radio waves, very very high frequency radio waves which have a very short range that they can transmit over before they are dispersed to the point where you can't really pick them

up anymore. So NFC, all of that transaction information gets carried over the electromagnetic waves when you tap your phone to whatever receptor you're using, whether you're paying for something, or you're exchanging information, whatever it is, it's being done electromagnetically, whereas in this case it's all being treads bit over

cellular data. So it's almost like like, really, this app in a way just removes the necessity for you to type in like the taxi cab number, because if if it's if it's all within a system, and each cab has a unique number associated with this is cab number, blah blah blah, you could theoretically just have an app where you type in the cab number and as long as you didn't make a mistake, you're fine, right, and

then you can pay that way sure. And and another way that this has kind of a head up over NFC devices is that uh NFC is a specific technology that you have to have a special device to transmit, and you have to have another special device to receive. Right. If your phone does not have an NFC chip in it, nothing is going to make that phone work with NFC, right. But but the technology behind this kind of thing is

actually really simple to implement. You don't even have to have a smartphone as long as your mobile device can can play m P three's for example, like like an MP three bedded in a text message. You can totally have this on on anything. I see your point. Yeah, yeah, I mean the same way that like Twitter is really cool because you don't have to have a smartphone for it. You can transmit messages to and from Twitter using text message. So this is really convenient for for that. For that reason,

I often forget that other people don't have NFC enabled telephones. Yeah, I don't think minus minus. I don't use it, but I haven't just so you can say you've got it. That's the only reason I have anything. It's just so I can say I've got it. So we're going to conclude this by talking about some interesting new research into sounds. So in the beginning of our last episode, we talked about how sound works from a physical level. Well, this is looking more at a very very granular level of

what's going on with sound. So I read this this interesting study granular I get what you did there, I'm sorry, and sing study about the relationship between sound and heat and magnetic fields. So let's talk about sound and heat first, because that's pretty easy to understand. Sure, Well, for one thing, the temperature of a medium through which sound is traveling, can change the rate it which sound propagates through it. Sure, because I mean when you think about it, sound is

when stuff vibrates, right, any sort of matter. When matter is vibrating, it's producing sound, assuming that there's you know, there has to be oxygen there or atmosphere anyway for us to be able to perceive that sound. But at any rate, when stuff vibrates, that creates sound. Sure, and vibrations are also what caused heat. Yeah, on an atomic level, that's what heat is. It's when atoms are vibrating, and the more the atoms are vibrating, the hotter the stuff.

So if you want to add more energy to a system, let's say that let's talk about sound first. So let's say you're either striking something with more force to create a greater amplitude, or you're striking something reg pularly to increase the longevity at which it will produce a sound. That's one way to uh add energy into a sound system. Or you add more energy for you know, creating greater

vibration of atoms, you're going to heat something up. You can see where there's some sort of relationship between heat and sound. Magnetic fields. However, that adds another element. How can manetic fields interact with heat and sound? Well, first you have to imagine that there is a fundamental particle of heat and sound called a phone on. And we're just using the word particles for simplicit No. I looked it up to make sure I did. It does sound crazy.

Now when I say particle, it's not really a particle. It's really more of a unit of measurement. Is probably the easiest way of saying it. But it's a way of describing a basic unit of vibration, the same way that a photon is considered a basic unit of life, except that's a physical thing kind of yes, physical issue for for a given definition of physical yeah, uh, and so phonon is essentially a unit of vibrational energy that

arises from oscillating atoms vibrating atoms. So uh. So it's not so much a true particle as a way of quantifying vibration, but we often refer to phonon's as the basic particle of sound or heat. All right, So it turns out that these actually can be affected by magnetic fields. How Well, if you use a really strong magnetic field on a non magnetic substance, you can actually control the flow of heat and potentially of sound through that substance.

That's what the researchers found. So what the researchers did was they took a semiconductor and they they subjected that semiconductor to a powerful magnetic field and found that they were able to reduce heat flow through the semiconductor by twelve percent. So the magnetic force was able to impede those phonons enough to reduce heat flow by twelve The implication here is that if you were able to use a strong enough magnetic field, then you could quote unquote

steer heat and sound, which could be incredibly useful. Uh, and you could affect non magnetic materials this way. It doesn't have to be something that's you know, that's that's ferress or that's magnetic. It just has to in fact, it it really just has to not be metal. The reason why it can't be metal is that metal ends up transmitting heat through electrons, a lot of heat through electrons, and it's so much so that if you were to use this method, any reduction and heat would be negligible.

You would not really be able to see the difference right, so they'd be like instead of being it would be at And also the other thing I have to bring up is that the testing conditions they use are slightly outside the parameters of practical everyday use. Uh. That being said, they used a seven Tesla magnet or a collection of seven Tesla magnets, which are the type of things you would find and say an m r I machine in a hospital or other like actual dedicated electro magnets at

a laboratory. It's not the sort of thing that you know, you kind of have a laying around your house. Sure, But so once I go in hijack an MRI machine, I can totally build one of these. Well, first you could, but then in order for it to actually have a noticeable effect the way it did in the study, you would first have two super super cool the material you were going to measure, because what they did with the semiconductor was they cooled it to just a little bit

above absolute zero. The reason is the phone on reduction is so subtle that if if it's warm at all, you can't see the effect. So yes, magnetic fields can have an effect on heat and therefore sound as well, because it can affect phonons. However, right now, the way that they have discovered it here, it's not something where you're going to be able to say, hey, I want the words I say to be steered directly to this

specific point. Using this methodology, you can use other tricks like interesting architecture to have sound transmit in really cool ways. I don't know if you guys have ever been in one of those science museums where they have the little kind of semicircular alcoves where you can sit across the room from each other and whisper and hear each other even if there's tons of other people in the room. Yeah,

so that's cool. We can do that through actually directing sound waves through through surfaces, but this would allow us to do it through magnetic fields. So imagine that you would be able to set up a system where, using these massive magnetic fields, you could dampen sound around areas That would be really no easy. Otherwise that could be really cool. Like I think of if I happen to live near here in Atlanta, we have like Chastain Park.

If I happen to live near Chastain Park and I didn't want to hear whatever musician is playing at Chastain Park that that time. Let's say that you know, it's it's just it's it's a Neil Diamond tribute band that's just playing really awful covers of Neil Diamond. Now, since I love Neil Diamond, it would break my heart to hear that, So I would want some sort of dampening field effect. That being said, we aren't talking about using

magnetic fields to steer heat and sound. So if you have anything that could be affected by a magnetic field, like all of your technology, it might be tough to implement. Like I also thought, oh, wouldn't this be great because I live across the street from train tracks, And then I thought, huh, there's a lot of metal train tracks and trains I've been a giant. Magnetic field would probably be the least effective means of it would probably actually make quite a lot of noise for a short period

of time. That would that would messen things up. Also, uh, getting you know, getting train yards down to absolute zero or so is yeah, no that you know. I I can find other ways to dampen the sound, I'm sure, like noise canceling headphones. We talked about us in the first episode two. So that wraps up our discussion. Now.

I want to stress, like, even the stuff we've covered in these two very epic episodes, uh, that's just scratching the surface of what sound could potentially do for us in the future, and applications of sound and interesting and innovative ways. There are tons of them, and I expect that I will be revisiting this several times in the future in the various videos for forward thinking, because they're

so fascinating and their potential is so amazing. Uh, And also just because it's so cool the thing of something we often don't associate with a physical force actually having that force. To me, that's really cool. So I I really enjoyed researching these. It's a lot of work, but it was a lot of fun too. I'm curious what our listeners thought. I would love to hear from you guys,

if you enjoyed this episode. Also if you have any suggestions for future episodes, we would like to hear them, Except we won't actually hear you will read them from your emails and you could send us an audio file. You could do that, but we might be a little careful with any files that are sent to us. I do not typically execute files that are sent to me via email, but you could send them to us on

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