What are the Craziest Applications for Lasers? (Including washing your dishes!)

But I think the real reason, and this is serious, was to uh to teach future aliens how to make keso in case they ever stop off at our moon, which is a serious bit of intergalactic hospitality. I think, wait, you're you're saying it's just the recipe, like the aliens will have to supply their own chips and cheese. I guess it's less hospitable when you when you put it way, But still the Mayor's heart I think was in the

right place. His name is Steve Adler, by the way, and the recipe he chose is a local favorite in Austin, and it was sent to the Moon as part of a lunar library that was stowed aboard a SpaceX rocket, the Falcon nine. Oh like they Okay, I was I was confused on how you were saying they had sent it. I was actually hoping they kind of like carve the case a recipe into the Moon, like with a laser or something. But I guess sending it on a rocket is that's a little bit more practical, I guess, yeah,

and a little less like cartoon supervillain. I guess that's true. All right, Well, then how does the laser fit into this? So the laser is actually what made the whole library possible, because they didn't just send a one page case a recipe to the Moon. The lunar library also included some other quote unquote light reading and it includes the entirety of Wikipedia um in English, tens of thousands of books, and a key to translate everything into five thousand different languages.

So sending a hard copy of all those things clearly wasn't an option, and instead the mission crew used a power full laser to etch the entire library, letter by letter, into this super light radiation proof nickel disk. And just in case the aliens who find to have bad eyesight. All the information on the disc was also laser encoded digitally, so the aliens can put it up on their view

screens or whatever they have. All Right, so all of this, like the laser ch case, a recipe, all of Wikipedia, this, this is all actually on the moon. Now, yeah, I mean there's a bit of a twist. The moon lander that was carrying the library crash landed on the Moon, and this was on April eleven, so so the mission wasn't exactly a success. But the good news is the

library probably did survive. According to a spokesperson for the Foundation, small light objects like our library do better and impact. It was probably thrown a few kilometers away a thirty million page frisbee on the Moon. I like to think about certain first like that, if you think about it, this was the first frisbee with a case of recipe on it ever thrown on the Moon. I mean that's pretty cool. Yeah, And and it was all made possible by lasers, which kind of sums up our show today.

When you think of lasers, it's mostly like death rays from sci fi movies and whatever. But as the Lunar Library shows, the truth is that real world lasers have much more interesting applications than just blowing things up, from levitating objects to precision cooking bacon. There are lots of weird things you can do with a laser beam, and we're gonna take a whole look at a bunch of them. Let's dive in. Y Hey, their podcast listeners, welcome to

Part Time Genius. I'm Will Pearson, and as always I'm joined by my good friend Manguesho Ticketer and on the other side of the soundproof glass, carrying on the show's proud tradition of thematic prop comedy. That's our friend and producer Lull. Just look at that mango. He brought in his own laser pointer from home, waving it around on pointing to all these different objects. I mean, it's not a useful tool in his line of work, but he's made the effort anyway. I mean, it's always putting in

the atah. I mean, it's that kind of spirit that we we really appreciate it around here absolutely. And and laser pointers are actually a good place to start because they really aren't much different from the lasers we use in research or defense. In either case you're dealing with the device that works by amplifying a highly concentrated beam of light a k A laser beam. So the main

difference between these devices is their power level. Right, The maximum allowance for a laser pointer in the US is a measly five milliwatts, but other kinds of handheld lasers can rage anywhere from twenty five milliwatts all the way up to a thousand. And that's what would have been used to edge the case or recipe into that disk, right, yeah, exactly, which is also why they're used for laser removals and and certain kinds of surgery. And those procedures aren't just

for humans either. For instance, I read that some aquariums has started using a seven d milliwatt laser to remove harmful polyps from their coral Apparently the laser can burn a poll up away so early that it won't ever grow back, and the whole process only takes about ten seconds. I mean, it does make you question at least a

little bit how safe these laser pointers are really. I mean, I know they're weak, but if you think about sort of like their larger cousins and destroying pole ups whole cloth and a matter of seconds like the five milliwott versions must do some small scale damage on their own, I would think, right, yeah, and and that's actually why you're never supposed to look directly into the beam of a laser pointer, because if you're to do that, which again you shouldn't, what happens is that a small portion

of your retina will be bombarded by like this highly focused light. And when that happens, the optical nerves get overloaded and you wind up seeing all these little floating spots. So it really is frying your retina, just not as quickly or decisively as like one of the stronger lasers, right and and so when we talk about modern lasers used for defense, it's that ability to temporarily blind and really disorient people that's in play. It's not like blasting

through armor or blowing apart buildings. For example, in law enforcement, there's something called a day their laser, and it's used for riot control. It's basically like a larger version of a laser pointer. It's about the size of a flashlight, but it's got a two fifty milliwatt beam and it's effective from about thirty yards away. So if someone looks into the beam, they can lose sight for up to

fifteen minutes and feel nauseous for even longer. So the idea is really to incapacitate a rowdy crowd all at once, and there's no need for physical contact, I guess. I mean, I could see how that'd be useful in some like really drastic circumstances, but it still feels pretty extreme to use these on civilians. But you know, there's one application where it seems a little more appropriate, and that's when ships use these dasers to ward off pirates. Have you

heard about this, I haven't. It's called sea lays, and the stock version is a whopping five thousand milliwatts, twenty times stronger than the flashlight that you mentioned, But if you want it beeped up, you can actually get one all the way up to twenty thousand milliwatts. So the base model alone, though, is strong enough to be seen

from nearly three months away. So the idea is that at a distance, you could signal the pirates not to come any closer, like a warning shot, basically, than if they continue to approach anyway, the daser's real effects would start to kick in. The pirates would find themselves nauseas, disoriented, and of course temporarily blind, which just doesn't seem pleasant. Yeah, and and that's like consumer grade tech, Like anyone on

the streets can buy the stuff. Well, they go for about a hundred thousand dollars a pop, so so maybe not anybody off the street, but anybody with a hundred thousand dollars in their pocket. They are available for civilians. Yeah. Of course, the military has their own brand of daser lasers, and these go back as far as the early sixties, when the first real laser was invented. Their early reports

of a so called I popper developed by the Air Force. So, according to this nineteen seventy two edition of the Post, quote the strangest of weapons was dreamed up in the early sixties as a means of exploding the eyes of an enemy soldiers and their officers from distances of more than a wile. Giant pulse lasers would sweep back and forth across the battlefield, blinding anyone who looked directly at it. That's sort of terrifying. Was it ever used in combat?

Thankfully not? I mean, the military eventually decided that exploding the enemy's eyes from a mile away might not be the most honorable form of engagement, And in and update to the Geneva Conventions actually banned the use of any laser weapons that cause permanent blindness, So this idea was actually put to rest. So weird that they're like rules to wark like that, But why don't we move towards some of the more wholesome ways to use a laser beam?

For instance, did you know that judges have started using lasers to help score gymnastics competitions. I had not heard this, and I'm curious why this is necessary, Like what was wrong with the old way of scoring competitions. So the main problem is that humans can sometimes miss important details when deciding the outcome of a sporting event. And that's

true even with instant replays. In fact, there was a study on gymnastics competitions, and this was back into thousand fifteen, and it concluded that up to sixty of athlete errors go totally overlooked by judges. And so the solution of that is to shoot a bunch of lasers at the

gymnast I guess, well sort of. I mean, there's this Japanese electronics company, it's called Fujitsu, and it's been working to develop three D laser sensors that can capture a gymnast movements and analyze them on the spot as I guess numerical data. So the idea is to use these recordings as a supplement to the judge's own observations, and if there's an error they didn't cash, the system will draw their attention to it. And if a judge ever needs evidence to back up a ruling, the system can

provide that too. I see. So then it's kind of like the motion capture that's used in the you know, the digital characters for movies like Gallum and Lord of the Rings. Is it kind of like that? Yeah? I mean, except in this case, the gymnast doesn't have to do backflips while wearing like a suit covered in those ping

pong balls. In said, there's a series of lasers that track their movements in real time and then transmit the data to a software program, and that way there's a detailed record of every move the athlete makes, no matter how fast or complex it is. And this includes everything from like the placement of their joints to the exact angles of their movements. That sounds pretty amazing. Actually, and

you said, this is already being used in competitions. Fujitsu announced the deal last fall with the International Gymnastics Federation and they've already tested the system at a handful of competitions this year, and and the goals really to roll it out in earnest at the Gymnastics World Championships in

late September. But beyond that, Fujitsu is hoping the laser system will become the go to tool for judges, not just for gymnastics, but also for things like figure skating or any other sport where they're like scoring inconsistencies and and involves decisions about precise movements. That's pretty cool, But I actually want to take us back to laser pointers for a second, because there's a practical use for them that I never would have thought about before we were

doing our research this week. And apparently home care nurses sometimes use common laser pointers as a way to enable their patients to communicate. So, say a patient has limited

mobility as well as difficulties speaking. In a case like that, a nurse might attach a laser pointer to a pair of eyeglasses or maybe the rim of a hat, and then the nurse would set up this communication board filled with common phrases plus all the letters of the alphabet, and you know, and the patient could express themselves by pointing to whatever it was they wanted to say. That's funny. It's it's like the simplest use of a pointer, but

it's also to communicate in such a specific way. It's so much more clever than, uh than you know, just using it to get a cat to run around a room. Speaking of which I know, we both found some scientific uses for lasers that were equally unexpected. But before we get into those, let's take a quick break. You're listening to part Time Genius, so we're talking about all the

surprising things you can do with a laser. So just keep in mind that even though you theoretically could do these things, you probably shouldn't do all, or actually any of them. The point you could use a high powered laser to heat a material to well over a million degrees, the atoms of that substance would cease to exist and you'd be left with a soupy mix of electrons and ions, what scientists lovingly referred to as plasma. But again, that

doesn't mean you should do that. So don't do that, Mango. Yeah, I mean you definitely shouldn't do that. Recreating the core of the sun in your living room is not recommended by this show. Well that's a good call on a less dangerous, but just as difficult side of things. It's also possible to use a laser to levitate tiny objects. So this is something I'm fascinated by, but it makes zero sense to my mind. I mean, lasers burn and melt and singe, so how could that possibly transfer into

making something float in mid air? I agree, I mean it's not very intuitive for layman like ourselves, but it helps to remember that light, including laser light, is made up of photons, and those photons exert a special kind of force known as radiation pressure, and that's really the key to what scientists call optical levitation. So when you have a really powerful beam of light, the radiation pressure it exerts is sometimes strong enough to overcome the force

of gravity. So if you aim a high enough power laser beam at a super light object, the force of the lights pressure can actually propel it forward or even lift it off the ground, which makes a little more sense to me. I guess. So, so are like solar sales an example of this, uh this technology, Yeah, that's it exactly. I mean most people have probably seen one.

They're they're like big gold colored square sheets attached to the end of a space probe or another small spacecraft, and the reflective surface harnesses radiation pressure from sunlight, and that in turn propels the craft through space. But you're saying it's possible to float something with a laser here on Earth as well. I mean theoretically, yes, the principle behind it has been proven in a lab setting, but

a real world test is still years away. And if that works, the researchers would be able to push around tiny particles that are too small to control through other means, and even cooler than that, they'd be able to power real life micro machines, by which I don't mean the tiny monster trucks that used to be popular when you were kids, even though those are just as awesome as levitating things, but rather things like flying a teeny tiny camera over a volcano or through the wreckage of a

building or something like that. That's pretty cool. Well, since you brought up radiation pressure, I do have to tell you about this other weird application Gabe told me about Basically, you can use to focused laser beams to create what's known as optical tweezers, and this allows scientists to manipulate objects smaller than a single micron, like a unit of measure that's equal to about thirty nine millions of an inch, or in other word, it's really really small. And and

so this works because of radiation pressure from the lasers. Yeah. So, so when you have a laser beam on other side of the object, the resulting forces actually work together and allow you to grip the object, so you can kind of think of it like laser beam chops six. That's cool. So, so is this something that was just recently discovered or what when Gay row up I I thought so too.

But but researchers first created optical tweezers back in the nineteen eighties and they've been improving on the concept ever since. In fact, the biggest limitation to the technology was finally overcome just a few years ago. For the last thirty years or so, there was always a cap on how finally you could focus a beam of laser light, and the result was that anything smaller than a hundred nanometers

couldn't be gripped by the tweezers. So I'm a little rusty on the micro measurements, like how small is that compared to the microns that you mentioned earlier. I'm embarrassed to admit that I'm a little rusty on these measures. Yeah, well, if I didn't have a shooting paper in front of you, I would not A hundred nanometers is equal to just point one microns. So we were already dealing with incredibly small forms of matter before that, like the organelles inside

a living cell, or or a particle of bacteria. But these are even smaller than those, and our laser chopsticks just couldn't get ahold of them. But back in two thousand fourteen, researchers and institute in Spain finally figured out how to focus laser light to such a fine degree that they could actually manipulate particles as small as just fifteen animators. And so what kind of stuff does that actually allow them to do so much stuff? Okay, enough said,

I mean, we'll never really understand. In fact, I'm just going to defer to scientific American on this one and and tell you that possible applications include, quote, building, medical products, with nano scale exactness, manufacturing nanocrystal geometries for electronic devices, and manipulating single molecules such as proteins. Right right, I guess that that sounds good, I think, but we've still got a few strange uses for lasers to talk about,

including a couple that are strictly just for laughs. But first, let's take one more quick break. Welcome back to part time Genius. Okay, Well, so we've talked about what lasers can do for aliens, and for sports judges and for scientists, but let's be selfish for a minute and talk about what lasers can do for us. All right, Well, how about this one. You can use a laser on your dirty dishes and have them cleaner than they've ever been before. Like,

say goodbye to your dishwasher. You really won't need it from here on out because of lasers. Well, in my family, I'm actually the one who washes the dishes, and I'm always looking for an excuse to throw out my dishwasher, So so tell me more. All right, So it's pretty simple, really, Like you talked about burning polyps off a coral earlier, and it's it's the same premise here. Except with all the grease and oil and mystery crust that gets stuck

to your cookware. You just install this device that kind of looks like really like a table lamp, I guess, and you put in your kitchen and then you never have to scrub another baking sheet or non stick pan again. You don't even have to control the laser by hand. It is totally automated, so the beam just scans back and forth over the pan or whatever it is that you're clean. It just burns the grease right off of there.

It's pretty amazing. Wait, so it's going to leave something behind right like, like it doesn't just vaporize all that gunk. That is true, like there should be some food ash left behind. But that's not the case actually, because the laser cleaner also comes with a built in nozzle that sucks up whatever the laser leaves behind. I mean, this is just amazing. And the coolest part is that these

two functions occur simultaneously. So the surface of the pan just goes from pitch black with grease too shiny and clean right before your eyes. It's like some kind of low key kitchen magic. It should totally be an informercial. This honestly feels like you're infomercial pitching. I am kind of also, I'm sold because you know, I'm the designated dishwasher and I hate scrubbing pans in the most It's definitely a pretty amazing invention. You can find the videos

of this thing online. You just look up laser age TV on YouTube and look for the laser cleaning of a baking tray. But if you do, make sure you turn up the sound because you can hear the food waste just sizzling away with every sweep of this laser. It almost sounds like an electric shaver or something, and it's all just weirdly satisfying. Yeah, I bet you know. I'm already sold. But my only qualm is if it's

kid friendly to have like lasers in your kitchen. Oh, mango, it is absolutely not kids, say, and it's it's really just for large scale kitchens and bakery is not something you'd want to keep around the house. In fact, this might actually be the strongest commercial laser we have talked about today. You remember the sea lays thing that ships used to scare off pirates, right? Yeah? Sorry, are you suggesting this technology? It can be used to clean pirates.

To you know what, that's actually a great idea, but it's not exactly what I'm getting at here. But as strong as that was, it maxed out at twenty thousand milliwatts. Well, the laser for this cleaning system is six times stronger at one and twenty thousand milliwatts. But if you want to know the real deal breaker, here's another scary umber. Forty thousand dollars. That's actually the going rate for your

own laser cleaner. I don't know, sending my kids to college for getting clean dishes and I have to wear it feels like an even trade. Possibly, but all right, well fair enough, So so tell me how this strikes you,

though mego laser cooked bacon. I'm listening, all right. So there's this mathematical science professor in Tokyo named Kintaro Fukushi, and a few years ago he partnered with a guy who runs a maker space in Japan, and together they designed this laser cutter that can perfectly fry the fatty part of the bacon, leaving the rest of it completely untouched. That's interesting, but why not cook the bacon all the way? Well, you could definitely set it so that the whole piece

of bacon was cooked. Like. The setup uses imaging software to build a map of each bacon strip, and then you can set the laser to aim at whichever parts you want. I love that this is like probably the most complicated way to cook bacon ever. But uh, I still don't understand, Like why would you want partially raw bacon? Like did they leave it that way on purpose? I mean, I love how much this is bothering you instead of

just focusing on the amazing technology. I mean, the truth is they left the meaty parts of the bacon uncooked for a couple of reasons. First, it showed off the mapping feature for their laser cutter, and second, it was a way of honoring the raw food tradition in Japan, like seafood is you know, the big example, but there are lots of traditional Japanese dishes that call for raw chicken or pork. Eating raw meat is much less common in Japan these days, but some people still prefer their

bacon only slightly browned. That's really interesting. I've never heard of that. Here's another unusual application for lasers I just learned about. According to the research from the Lincoln Lab at m I T it's possible to beam a secret message directly into someone's ear using a laser. So you can actually be walking along and all of a sudden you hear a whisper in your ear, But it's not coming from the person next to you. It's coming from

someone eight feet away that you haven't even noticed. Who just shot a laser at your ear. That is so creepy sounding. So how would this even work? Like, what do lasers have to do with transmitting sound? According to the research team behind this, it works because laser light excites the moisture in the air around the target's ear. So basically there's a phenomena called the photoacoustic effect, and because of that, the water vapor in the air will

absorb the lasers emission. And then what that produces sound? Yeah, the water vapor gets so excited by the laser that it actually starts to vibrate an audible frequency. All right, So let's say you live in a dry climate, like with this not work there, I feel like I might have to move to a desert just to escape this weird thing. Well, it actually does work there because even if you're somewhere dry, there's still usually enough water in

the air to produce the effect. You maybe wouldn't hear it as strongly as you might in wetter environment, But even then, the researchers think the volume of the sound has more to do with how well the water absorbs the sound, rather than how much water there is in the air. That's terrific, you know, I'm still trying to decide if this is fascinating or horrifying. Like, on one hand, it would be pretty fun to beam whispers back and forth without leaving a paper trail or like disturbing people

around you. You can even have a conversation from across a crowded room, which would make for like an amazing party trick or a spy trick or whatever. But on the other hand, it's easy to imagine like companies beaming ads into our ears at all hours of the day. Like imagine walking past a coke at at a bus stop and it triggers this like motion sensor, and as you walk away, you hear someone like playing the company jingle in your ear, and things could start to feel

super dystopian like pretty quickly. With something like that around, Wow, I would be pretty unnerving. Yeah, it's it's so weird, right, But but amazingly, that's not even the scariest potential use for sound based lasers. Wired had this article recently about how hackers will soon be able to use lasers to speak to any kind of computer that uses voice commands. So we're talking smartphones, tablets, even home assistance like Alexa,

Siri and and Google Home wes. You're saying the microphones and those devices will respond to the light of a laser just like they would respond to a sound. Exactly so, according to the researchers who discovered this was possible, if you point a laser at a microphone and change the intensity to a precise frequency, the light will somehow stimulate

the microphone's membrane at that same exact frequency. They are completely sure yet what causes this light as speech effect, but the result is that the microphone reads the incoming light as a digital signal, just like it does with sounds. So if you were in a room when this happened, you wouldn't actually hear anything. The laser voice is completely silent, but the microphone inside your device would respond as if

it had just received a voice command. All right, So what about the voice assistant that's on your phone, Like, like on my phone, series only responds to commands if I'm the one who speaks them. So does that make smartphones immune to these kind of laser attacks? I mean, they've got a slightly better line of defense than smart

speakers like the Amazon Echo or the Google Home. Those don't have the kind of voice authentication you're talking about, and that makes them especially vulnerable to light commands from hackers. But that said, if a hacker had a recording of your voice or was somehow able to reconstruct it, they could actually adjust the frequency of their laser to match the sound of your own voice and then use the to issue commands to your phone. So what what kind

of commands are we talking about? Exactly? I mean, it's terrifying. They can make online purchases, unlock your car, adjust your thermostat, open the garage door. It really just depends on the kind of system that's being hacked and what the user has it hooked up to. And the worst part is, because of how intense a laser beam is, hackers could use this trick even on devices that are hundreds of feet away. So if you have a home assistant that responds to voice commands. Your best bed is to keep

it away from any windows. If it's in the hackers land of site, then it's in the land of their fire too. Yeah. That's that's interesting. You know, I thought we were selling a dishwasher laser in this show, but it turns out we're advocating for really heavy curtains and blinds. I feel like at this point, I mean, it really all goes back to what we were saying earlier. Just because we can do all of these things with lasers

doesn't mean we should. I mean, for my part, I think I'll just stick to using them to point at things and we'll leave the rest to the professionals. Yeah, that's probably a good idea. But before we bow out of this laser game for good, let's fire off a few more rounds in today's back off. Yah yah h m okay. So I wanted to start with this one because it's something I always forget, which is that the word laser is really an acronym. It stands for light

amplification by stimulated emission of radiation. And the other weird thing is that most of that name was actually taken from an earlier technology that amplified microwaves instead of instead of light waves. So some mazers, I guess, yeah, exactly. I I used to think masers were some kind of made up science fiction version of lasers, like in the old Godzilla movies, the military always rolled out these tanks with satellite dishes on them to to fight the monsters,

and they were called maser cannons. But it turns out that those were a real thing, and they actually predate lasers by about a decade or so. Plus they're effective against Godzilla, which isn't nothing. I mean, that's that's impressive. Alright. Well, back to lasers. If today's show has you craving a few more lasers in your own life, you could always head to No Man's Land for the most remote game

of laser tag on the planet. So Originally built during the Victorian era, as this British sea fort, the aptly named No Man's Land is an artificial island that never saw much action and was ultimately decommissioned during the nineteen fifties. So from there. The fort had a single brush with fame back in the seventies, when it served as a location for a doctor who episode, apparently it was home to a race of these evil bipedal reptiles called the

Sea Devils. Then, in two thousand fifty No Man's Land entered the strangest chapter yet when it was converted into a luxury hotel and entertainment resort. These new features of the fort include twenty two bedrooms, a cabaret bar, a sauna, plenty of shops and restaurants, and of course, a twenty one room laser tag labyrinth that winds through the entire lower level. And if you think about, like, who doesn't want to play laser tag in the basement of an

abandoned sea fort, it just sounds pretty awesome. Um. In November two thousand seventeen, a British laser lighting Companies set the world record for the largest laser light show of all time. This is at a convention in Las Vegas. The company made history with a thirty minute laser show

that featured to staggering different lasers. The show culminated in a seven minute finale that lit up the Nevada sky with a massive one thousand, three d seventy seven watts of laser power and again for reference, the average laser pointer uses just five milliwatts. Yeah, that's a lot of juice.

That's that's interesting, all right. So we've run through a bunch of different applications for lasers today, but back in the sixties when they were first being developed, no one was really sure how you could actually use these things. In fact, the inventor of the laser didn't even really know. His name was Theodore Maymon, and despite building the first functioning laser for Hughes Laboratories in nineteen sixty, he later referred to his creation as quote a solution seeking a problem.

And the good news, as I think we've shown today, as they're turned out to be all all kinds of problems that lasers can actually help solve. Yeah, that that is true. But I have to point out there's at least one major problem that lasers could potentially create in the future, and that is, of course, the warping of space time. You know, I thought for sure this was gonna be about some like real life death star or something. But what do lasers have to do with space time?

So this all comes down to gravity. Light carries energy, and because of that, light has its own gravity. But the gravitational force created by laser light is scientifically speaking, a little bit funky. It turns out that when you rotate a laser beam, it's gravity actually warps the nearby spacetime, which you might recall is basically the fabric of the universe. So as the beam rotates, spacetime curls along with it.

And I know this all sounds kind of scary and world ending, but don't worry, because the researchers behind this discovery have a much less upsetting way to think about it. According to them, the reality warping effect is like if you put a ball into honey and spin it, the ball kind of drags along the honey around it. You know, I'm not sure that's any more reassuring, but it is fun to imagine the fabric of the universe is honey. So I really feel like for that alone, you've earned

the trophy for this week, Mango. Congratulations. Well, it is an honor. As always, I do think we should thank Gabe for doing the heavy lifting on this episode, as he does for most episodes. But but lasers are so complicated and you did so much research for it. But I think that's it for today's part Time Genius from Will gave Lowell and myself thank you so much for listening. We'll be back next week with another new episode. Part

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