Big mysteries explained through your senses

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And even change you. I literally feel like I'm a different person. Yes! Do you feel that way? Ideas Worth Spreading from TED and NPR. I'm Minouche Zomorodi. Today on the show, how our senses can reveal things about ourselves and the world around us that might otherwise remain invisible, starting with what we can hear. Roughly 13.8 billion years ago, the universe began. We call that moment the Big Bang, except it didn't make a sound.

The term Big Bang does suggest an explosion. It suggests a sound. But things are a little bit more subtle than that.

This is Mark Whittle. He's a professor of astronomy at the University of Virginia. And the first thing that Mark wants us to understand is that the Big Bang wasn't an explosion per se, at least not like in the movies.

It was really in a way that The expansion not of something in a preexisting space, but it was the expansion of space itself, carrying material with it. And so paradoxically, the Big Bang was probably in a way silent because everything's moving away from everything else. There are no pressure waves.

Pressure waves. That's what sound is. Right now, as I speak, tiny molecules are moving through the air, But if there's nothing to move through— no air, gas, or water— then there is no sound. So the universe, in its first few moments, was silent. But then, as it expanded, things changed.

In the young universe, you did actually have a gaseous atmosphere pervading everywhere. That was the nature of the young universe. It was hot, but there was a gas, and through the gas, sound waves can move.

So the Big Bang itself The Big Bang itself may have been silent, but almost immediately afterwards, the universe got noisy.

The acoustic era started almost immediately, basically, and extended for about 400,000 years.

400,000 years might seem like a long time, but compared with the nearly 14-billion-year life of the universe, Mark says it's roughly the equivalent of its first day. And during this period, the acoustic era, Certain areas of space had more matter than others. Gravity pulled gas towards those denser regions, compressing it, bouncing it back out, pulling it in again, over and over.

What you have there is an approximately spherical sound wave being created by gravity pulling gas into these slightly denser regions and away from the slightly less dense regions. So you have this whole set of compressions and rarefactions.

This created sound waves moving through the entire young universe. Of course, no one was around to hear them. And even if you somehow could have been there, your ears would have been useless.

The frequencies of the waves that I'm talking about are one wave every 50,000 years. So, I mean, you wouldn't even live to see one wave pass you.

But what if we translated those waves into something the human ear can perceive? What would the beginning of the universe sound like? What you're about to hear represents the first 400,000 years of the universe, compressed into about 10 seconds and raised roughly 50 octaves into the range of human hearing. Thanks to Mark Whittle, it's like we can hear the universe expanding.

So the most obvious thing is this decrease in pitch, the drop in pitch.

Mark says imagine the young universe as an enormous musical instrument, almost like an organ. At first, only its smallest pipes had enough time to produce waves. But as the universe aged, larger and larger regions joined in. And larger pipes make deeper notes.

The musical instrument, if you like, of the universe is beginning to wake up. And it wakes up in sequence, starting with the smallest organ pipes and ending with the largest.

Our senses are how we make contact with the world around us. We use them to navigate everyday life. But they can also help us understand things that seem almost impossible to comprehend. So on the show today, a journey through the senses: what we can hear, see, feel, and smell, from an artist translating modern-day challenges into physical art experiences, to a chemosensory researcher exploring the science of smell, and using sound to understand the expansion of the universe. Which brings us back to cosmologist Mark Whittle. Mark has been obsessed with astronomy since he was a child growing up in England.

I was lucky in being a sort of 10-year-old in the mid-'60s when a lot happened in astronomy. And I also happened, just happened to be living in Cambridge in England, and some of what was going on was happening there. Discovery of pulsars, these sort of rotating neutron stars, discovery of quasars. So these were huge black holes, you know, far across the universe. And then of course, you know, the famous discovery of the, of the microwave background, the, the fireball of the Big Bang. And they all happened at roughly the same time. I had a little box that I put, you know, articles that I'd cut out of the newspaper and little paraphernalia.

I love it.

Your own little Google.

That's— yeah, yes, way predates anything like that, but that was my little way of doing it, and it fascinated me, and I don't think I've ever looked back.

Can we just lay some groundwork? The Big Bang has really become one of your specialties, explaining and talking about that. But when I was a kid, it was presented as a theory of one of the things that may have happened to create everything around us?

So certainly, I mean, of course, there's a famous TV show called The Big Bang Theory, and the word theory's attached to it. Nowadays, I would say there was sort of, oh, maybe 5 or 6 just really key pieces of evidence which support the reality of a hot early phase in the universe's life, roughly 14 billion years ago. And, um, you know, maybe the most obvious is the microwave background. Um, it's essentially the, the glow coming to us from those early times across space. But when we look out, we don't see that light directly.

Mm-hmm.

The light waves got stretched as they crossed the expanding universe. And so they started out as light, leaving the young universe with wavelengths of about a millionth of a meter. That's a micron. And they arrived 1,000 times longer. And sure, it's a millimeter, and those are microwaves. So it is light that left the young universe, but it's microwaves that arrive. They've had a very long journey, you know, 14 billion years. And during that time, they've been stretched and they arrive therefore as microwaves. And that wavelength, of course, we attach the name microwave. It's the same, basically the same type of waves that are inside your microwave oven.

Yeah, so I guess that brings me back to my question about the name, the Big Bang. I mean, call me literal, but I always assumed that meant there was a loud explosion.

Yes, so let's just look at the coining of that term, uh, the Big Bang, which was sort of 1950s actually, and it goes to a series of radio programs broadcast on the BBC where a prominent British cosmologist called Fred Hoyle was actually doing an excellent job communicating These are all these new discoveries. The implications of new galaxies forming are striking. He coined the term Big Bang to be slightly derisive, just saying, well, it's nothing more than a big bang, really. And that name, that name has stuck. There are actually many Big Bang cosmologies, and they all have the property that the universe is supposed to have started at a particular moment. But the creation of the universe in this So-called Big Bang was really rather different. It involved— and it's difficult to get your head around this— but it's really not of an expansion into anything, it's an expansion of everything.

God, it really messes with your head, doesn't it, Mark?

Oh, yes.

So how did you come up with this idea of translating all your measurements of these sound waves into music, something that is We can listen to.

So starting with the COBE mission, that's a NASA satellite in 1990, and then the WMAP satellite in 2003, the sensitivity of the microwave telescopes began to reveal these very slight patches on the microwave background. And what scientists do with the image of the microwave background, this full sky, this sphere of glowing with patchiness on it, is they do a wave analysis of it and it produces a spectrum. And not only were these waves basically acoustic waves, but also there was a fundamental and harmonics. And that is exactly the signature of something like a musical instrument or a human voice.

I mean, it brings new meaning to the phrase feeling like you're in harmony with the universe, right?

Yes, absolutely. I mean, it's a— yes, they're both harmony sort of Emotionally and aesthetically, but also acoustically.

Yeah.

And so I just thought it was a wonderful way of communicating to the, to the public what this— these new discoveries were, was to actually use sound as the bridge rather than light. Because everything, for the most part, as you, as you said, is visual. You have the wonderful pictures from, you know, Hubble and other telescopes. They're all visual and they're color, and that triggers our, you know, our sensitivity to color. But our ears are not often used, and so I thought, well, here's an appropriate vehicle.

Now, here's a map of today's old universe spanning 4 billion light-years with us at the center, and it shows the positions of about 100,000 galaxies.

Mark Whittle explains more from the TED stage.

And if you perform a similar wave analysis, sure enough, there's the fundamental and harmonics showing up faintly in those web-like patterns. The sound waves have turned to stone, so to speak, and become fossilized in the patterns of galaxies. But even more remarkable, I think, is that we think all of this cosmic structure, the sound waves and the galaxy patterns, had their ultimate cause with subatomic quantum vibrations during the universe's birth process, an incredibly short time of hyperexpansion that we call inflation. Now, this is a truly stunning proposition, that quantum oscillations smaller than atoms get amplified by cosmic expansion to make huge sound waves that then transform into an ever-expanding tapestry of galaxies.

In a minute, more about using sound to help us understand how the universe began and turning the mysteries of On the show today, making sense of the invisible world around us. I'm Manoush Zomorodi, and you're listening to The TED Radio Hour from NPR. We'll be right back. This message comes from CookUnity, the first chef-led meal delivery service where every meal is handcrafted in local micro-kitchens, not mass-produced in large facilities. With hundreds of There are hundreds of dishes to choose from and over 10 different dietary preferences like high protein, low sodium, GLP-1, and more. Taste what happens when real award-winning chefs make fresh, small-batched meals just for you. Go to cookunity.com/radiohour or enter code RADIOHOUR before checkout to get 50% off your first order.

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It's The TED Radio Hour from NPR. I'm Minouche Zamorodi. On the show today, making sense of the invisible world around us. Cosmologist Mark Whittle has spent decades explaining the creation of the universe to his students at the University of Virginia. But he's also been using sound and music to help the public at large connect with these mind-blowing concepts. Earlier, we heard those ancient sound waves turned into something that we can actually hear as humans. But Marc also wanted to know, could those sound waves be turned into actual music?

Yes. So in this period in the early 2000s when the data were coming in and the first 3 harmonics were seen, and then more recently with the Planck mission, And the first 7 harmonics were seen, um, you know what, I began to sort of play with it a bit more and sort of measure, well, what are the frequencies of these, what are the tones? And, um, as you heard from that rendering of the raw sound, it's really more like noise than music. And that's for a very simple reason, and that is that the young those harmonics coming from the young universe are actually very wide. You know, if you're standing at a piano, you don't put your finger on one note, you put your full forearm onto a lot of notes. It all comes out together. And so it's not very musical and it's more like noise. And so, you know, I just thought of the simple modification really, which was to narrow the harmonics, bring them down to the kind of width in frequency, in pitch, that a musical instrument has, and that's very much narrower. And so then it becomes more like a note, and then you start saying, oh well, what were these notes? What kind of chord was it? And then I also thought, although it's continuous sound, so it's, it's, uh, I mean, the technical term is microtonal, so they're not individual notes, they— it slides down. I just thought, well, why not map it onto all the notes that we know about.

We want to play it, if that's okay.

Yeah, sure.

So in simple terms, what did we hear there?

Yeah, so that was the, um, the sounds that, that come from when you track the harmonics dropping in pitch as they cross each note on a piano keyboard. So, uh, or instead of sliding down, they're now sounded at particular moments just depending on when they cross that, that note on the piano. And those are the first 8 harmonics, which are, which are basically the, the 8 that have been seen by by telescopes. And, you know, I chose to sound those using a piano, but it's still not particularly sort of orchestral and musical.

To finally add artistic expression to this, I gave these notes to sound artist Ander Mikkelsen, who worked with Pulitzer Prize-winning composer Caroline Shaw to write a work for choir and organ lasting about 10 minutes, and based on these note sequences. It's been performed a number of times, but here's a brief excerpt from a performance in the Catholic Cathedral in Richmond, Virginia. O, say, does that star-spangled banner yet wave I think this is one of the few times I've experienced a genuine coming together of science and art, both framed within a sacred context. It was a moment to feel deeply connected to and part of the entire universe. Those And particles and atoms from that first acoustic era went on to make stars and galaxies and planets and, of course, us. And right now, some of those atoms are inside your brain, somehow witnessing and understanding their own ancestry. They were out in that hot glowing gas, participating in that first symphony. Nowhere else, as far as we know, can the universe appreciate itself.

It's intense.

Yeah. Yes, the piece lasts 10 minutes. I picked that because I thought it demonstrated the range, and including that lovely transformation towards the end of that excerpt where it gets, you know, just delicious. It's lovely. And actually, I think there's something really sort of almost philosophically rather delicious here, which is that it turns out that most of the cosmological story and most of science in general is actually intuitable. And there's, in a way, we have no right for that to happen because we've evolved in a very different environment on the surface of the Earth. What What sort of— why is it that we can understand and translate these things that are so remote into our world? And I think the answer is because actually, you know, all the laws of physics are right here on the surface of the Earth, and we've sort of been coached in them through our evolution so that, yes, we know what sound waves are and we know what light waves are because we've developed senses, and the universe is filled with those 2 things. and more. And so actually, we've got a very rich intuition for most of the rest of the universe, even though we've only been constructed on this tiny little sphere. We've come from that material. The material that was making the sound has become us. I mean, not just us, it's made a lot of stars and galaxies, but—

Mm-hmm.

Our material was out there in, in the, in that hot gas, and extraordinarily, for reasons which we really don't understand, that same material can now actually understand itself and witness its own origins and at some level appreciate them. And that seemed to me to be a rather beautiful loop from The unconscious early universe sort of becoming awake through us and our ability to somehow understand our surroundings enough to appreciate the deep lineage of how we got here.

I mean, I love hearing about this because it just takes me out of my minute-to-minute worries And it's easy not to think about this stuff because I don't understand it, but then I'm reminded by someone like you who does extraordinary projects like this that no, actually we do understand quite a bit of it. Sure, we don't know the why or the how, but there's so— but science is unraveling and can be made more sort of tangible to regular people.

Absolutely. I basically spent my life doing my childhood hobby, which is incredibly lucky to do that. And through that exploration of astronomy, I actually can, without any real effort, just sort of see the universe around me. I mean, just to give you a quick example, you know, I went for my Morning walk, and I, you know, as each foot lands on the pavement, you just think, well, what is that material that my feet are landing on? It's hard, and it's got, you know, magnesium and silicon and oxygen. And then you think for a moment about, well, what are those things? Well, they're made of atoms, but go inside the atom to get to the nucleus. There's a bundle of protons that are stuck together. How the hell did they get together? Because they push each other apart. And the answer is, well, they got pushed together in the centers of stars about 5 billion years ago, where they, you know, the, the pressures were enormous and the temperatures flung those protons together. And then they got, you know, expelled out into the coldness of space. And then 4.5 billion years ago, it all collapsed in an incredible crash onto the Earth. And through billions of years, here they are now under your feet with every step. And they have that history locked inside them. And that's remarkable, to come out of a morning walk down the pavement, but it's all there. Just the enormity of the universe and its incredibly varied environments that can create all these things and then bring them together and mess them around in a big cauldron, and out we come.

Mark Whittle is a professor of astronomy at the University of Virginia. You can see and hear his full TED Talk at ted.com. On the show today, ideas about using our senses to navigate and understand the world, including our sense So when it comes to the evolutionary purpose of smell, you know, it's survival. Polly Joseph is a senior investigator at the National Institutes of Health, where she co-directs the National Smell and Taste Center.

I study how important smell and taste are for health and well-being.

Polly says smell is the body's early warning system, detecting things way before we become consciously aware of them.

So it detects airborne threats like smoke, fire, toxic chemicals that are in the environment, including predators, before they can be seen or heard. It also helps determine if food is safe to eat or dangerous. So you can think about that as, like, one of these evolutionary systems that has been preserved across species.

So smell can alert us to danger in our surroundings. But over the past decade, Polly has been studying how smell can be an early warning system for things that are happening inside the body as well, specifically the brain. It all started with her mother-in-law's cooking.

Her food started tasting very salty or very sweet, you know, An excellent cook, amazing, delicious Mexican cuisine, and she's Mexican, but we started noticing this.

So she would make you a meal and you'd be like, whoa, everything is super salty or really sweet.

Yes. Even the kids will notice it was extremely salty. And, you know, one of the things that she was also starting to do and compensate was like she will ask us to taste the food for her.

Ah.

Like, how does this taste? So I tell my— I turn around and tell my husband, I think something's wrong.

Paule knew exactly what to do. She got a booklet of scratch-and-sniff stickers to test her mother-in-law's sense of smell.

And then that tells you, you know, depending on how you answer, that tells you whether you have decreased sense of smell or complete loss of smell or whether your sense of smell is normal.

Huh!

And lo and behold, for her, It was a decreased sense of smell. And that kind of sort of led to a cascade of doctor's appointments and a number of tests. And then we realized that, you know, she had frontotemporal lobe dementia.

Is that because it's the same region in the brain that's being affected?

Correct. So it's like the areas of the brain that are being affected, you know, are sort of degenerating this— the olfactory patterns as well. So in particular, you know, for her, I mean, we noticed this early. So we see that in individuals with Alzheimer's and Parkinson's disease, and even frontotemporal lobe dementia, the sense of smell is decreased early, like years before any other symptoms appear.

Years before?

years before any other symptoms appear. So for many people, we are not getting, you know, we're not getting our sense of smell measured by our primary care doctors. I mean, if I ask you, Manoush, when was the last time you had your sense of smell measured?

Never.

Never. That's usually the answer that most people give.

That is true. That's funny. I just had my checkup the other day, and he checked, you know, my tongue and looked in my ears and my eyes. And measured, you know, my, my body temperature and weight. But there was— that, that was the one sense that we had no discussion about, my sense of smell.

Exactly. So, and, you know, and your provider is not alone. You know, we have school vision screenings. For hearing, we have the same. For smell, we have instruments, and they're good ones we have, but they're primarily used in research, and no specialty really owns it. There's no reimbursement. And until recently, there was not much to offer people once you found out there was a problem. So, if you ask me who should be doing these tests, I would say, at a minimum, primary care should be screening and then doing the proper referrals.

So, just like, you know, I get my cholesterol done every year and I have a baseline, we would know, like, oh boy, this is skyrocketing and we need to do something about it.

Exactly.

But what is the difference between regular loss of smell and taste Based due to aging versus, uh, it being a symptom of something much, much more wrong, deeply wrong?

Yeah. So, you know, one of the things, like, our senses are going to decline as we age, but one of the things that happens when, you know, neurodegeneration is that even though it's slow, You can see those changes most— more pronounced in, in some ways for some patients.

Mm-hmm.

And it's really tied sometimes to the, to cognitive decline as well. So, I think what matters is not whether your smell is perfect, is whether it changed, especially if this change is suddenly, or, and it has not come back. And, you know, when you think about, for example, COVID, COVID was actually a very interesting ex— you know, social experiment when it comes to smell.

Yeah, because I feel like for many of us, that was the strangest symptom, which was people immediately losing their sense of smell, something, you know, not like with a cold where it's dampened, but like completely gone.

Exactly. You know, and one of the things that we have seen with COVID is like, You know, most people recovered, but we've seen that a small group did not. And some of them have developed parosmia, which is an absence of distortion. For example, your coffee smells like burning garbage.

Ugh, no, that's so sad.

Yes. So, you know, you know, their own partner smells wrong.

Oh, no.

And that's harder to live with than losing it altogether. And that gets badly underestimated because it sounds minor when you say it out loud, but it is really, it changes your quality of life.

You know what it actually reminds me of is when I was pregnant and I would walk by bakeries and normally I would love the smell of bread baking, wafting through the air, and it made me so nauseous and it was such a strange feeling. What is happening when something actively smells bad that used to smell good? What, what is going on in the brain?

So actually, currently, we have a study that we have that it's ongoing right now, which is really, we're trying to understand exactly this question. You know, what happens when someone develops parosmia? So we're getting individuals with parosmia and putting them inside a scanner. To understand through, you know, fMRI, just scanning their brain, what, you know, what signals are changing. So we can really understand why is this distortion happening and what can, and what are the mechanisms and is there something that we can offer patients that can ameliorate their symptoms. If you go to the doctor, they will say, you know, it's in your brain. No, this is an actual experience that someone is having.

In a minute, more about your sense of smell and what it means when it goes away with chemosensory researcher Polly Joseph. Today on the show, how our senses help us understand our surroundings. I'm Minouche Zamorodi, and you're listening to The TED Radio Hour from NPR. We'll be right back. This message comes from Pure Insurance. When shopping for home insurance, reviews and prices are common considerations. But what about the motivations of the company behind the policy? Pure Insurance is motivated by its members. That guides the decisions Pure makes every day, including who benefits when the company does well. To date, nearly $170 million has been allocated to members. Learn more and see what membership means at pureinsurance.com. Privilege Underwriters Reciprocal Exchange.

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It's The TED Radio Hour from NPR. I'm Minouche Zamorodi. Today, we're talking about how using our senses, including sound and smell, help us better navigate and understand our world and ourselves. Polly Joseph is the co-director of the National Smell and Taste Center. She's researching why some illnesses cause our ability to smell to suddenly disappear and the effect it can have on people's lives.

One person that comes to mind, you know, is this young man who was a firefighter and lost his smell to COVID. And as you can think, you know, being exposed to things like, you know, smoke, And burn, you need to be able to smell this.

Right.

So, one of the things that really was causing him a lot of distress was the fact that he wouldn't be able to do his job. Like, he was— and at this point, he was being diagnosed with long COVID. He was not recovering. And we really needed to start thinking about this as a disability. This is one of those things that we consider an invisible disability. And he had to change, he had to think about different accommodations at work because he couldn't necessarily, you know, work in the field anymore because of this. And I had a, an, another patient who was a chef. And as you can think, you need your sense of smell and taste as a chef.

Yeah.

And just the deep grief that, you know, these 2 individuals' experience as a firefighter, as a chef, their community, like things were changing so quickly for them, um, just because the senses that they needed for work were, was just gone. And till this day, they have not recovered.

Oh, they haven't? Yeah, I was going to ask, is there anything you can do for them?

So We don't have a lot of treatment when it comes to, to smell and taste. We primarily have, um, you know, olfactory training is one of the things that we tend to recommend to individuals. And it works for some people, but it doesn't work for others. We need to know exactly, you know, the, the reason, like what caused the loss of smell. And how early are we catching people? And if we catch it early, we see that if it's based on a virus, you can— it can regenerate and people can gain their sense of smell back. But for others, it just doesn't happen at all. So this is why we have been focused through, you know, through the National Smell and Taste Center and some of the other centers around the country.

Mm-hmm.

on really understanding what is happening. What are the mechanisms? What are the things that are changing from a biological perspective so we can develop drugs and treatments and interventions that can help people long-term? And if we understand this, we might be able to create alternative therapy that can help also people preserve their brain health through their sense of smell.

Can you tell us more about the research you're doing where you're linking it to obesity and alcohol use disorder in addition to neurodegenerative diseases? What— how does that fit in?

Yeah, so one of the things that, um, when we think about, for example, alcohol, we think about cravings. The smell of alcohol gives individuals cravings, but one of the things that we have not really looked is to, you know, how are the senses affected by long-term alcohol use? So one of the things that we are looking in, in, in my lab in particular is, you know, what happens when sustained drinking and what happens when individuals stop drinking is their recovery of their sense of smell and to what baseline.

Hmm.

And it's the same thing, um, with obesity. So you probably heard a bit of like, you know, the changes that are occurring right now when individuals taking GLP-1s. So, you know, just as of this month, there's been some study just showing that, you know, everybody assumes that these medications make food taste bad or taste like nothing. And that's not what this group of investigators found. Smell was unchanged. But the main difference showed up in something called detection threshold. It's just a degree of sweetness that you, or for example, that you need to be able to detect something. So that's one of the things that changed for individuals that actually had, that were taking GLP-1 and what we call food noise. So people on the medication longer reported, you know, Fewer intrusive thoughts about food and less craving, less reaction to food cues, and less wanting high-fat foods than, than those that didn't. So, but when it comes to the particular changes in the sensory processes itself, we need more studies on this to understand how the world is changing for people on taking these medications. Mm-hmm.

So just to sum it up, I think what you're saying is that this study is saying it's not just how hungry you are, it is how things taste when you do eat them, what they smell, the sort of— the textures, whether you are thinking about food, whether it feels as satisfying when you do eat it. Everything.

Exactly.

Yes. I would love you to just sort of tell me what you, on a daily basis, just like in our everyday lives, Do you think that we should put more of an emphasis on smell? Do you think it could change our experience of the world? I mean, I've never been that into aromatherapy, but I don't know, you're making me think maybe I should be.

I mean, I think we need to be more conscious and, you know, like, I think mindful about this, the odors around us. Stop and smell the roses. It is important for us to do this, right? Like, to be to do more active, like, olfactory training. Like, you can do this even when you're cooking at home, right?

Mm-hmm.

Just get something out of your cabinet when you're putting the spices in, you know, in as you're cooking your meal. So it's not only just about aromatherapy, it's even in the way that we are interacting in our kitchen. There's so many places around Our lives, where smell is actually playing an important role.

That was chemosensory researcher Polly Joseph. She is a senior investigator at the National Institutes of Health, where she co-directs the National Smell and Taste Center. You can watch a video about her work at ted.com. So on this episode, we have talked about sound and smell, and now how sight can help us comprehend The nearly incomprehensible, like how our planet's climate is morphing and changing, or the sometimes scary and very confusing capabilities of AI.

We are the reason for all these complicated problems. We made it, but we don't even know what is happening, how to understand it, how to solve the problems.

This is Yiyoon Kang. She is a multimedia artist based in Seoul. And in her work, she tries to span that gap between humans and the forces we've created that we can't even see.

So the first thing I believe that we could do is make the problems ours. And to do that, I think we need to feel it. We need to sense it.

I saw Yiyun's talk in the TED Theater. She was an ethereal figure on stage, almost as though she'd been brought there from the future, surrounded by shifting light, lasers, and enormous moving images. Her work takes things that are mostly invisible to us, like satellite data, artificial intelligence algorithms, and gives them a shape that people can actually see.

Living at the intersection of art and technology, my mission became clear: to render the invisible visible. But how do we translate the intangibles? Let me take you on my journey. I began with the most vital dataset: the Earth. Specifically, our water. Half of humanity will lack clean water by 2050, and many already do. To expose the crisis of this vital resource, I spent an intense year with Google. They were searching for an artist who could bridge the gap between complex data and creative storytelling. And an amazing door opened. NASA joined the team to offer me exclusive access to the satellite data. This rare gift becomes the soul of my artwork, passage of water. My goal is to turn these NASA numbers into visceral experiences, dramatize them so that we can truly see and feel what is happening to our freshwater. Look at this. This is the raw satellite data that captures the water situation.

At first, the raw data is not exactly moving. On 3 enormous screens, it looks like what it is: columns and columns of tiny white numbers racing around.

We have the most sophisticated technology of our time, but who can actually understand what is happening here? What happens if we change the interface? This is Passage of Water. It lives on Google's platform, designed for you to fully interact with.

Picture planet Earth floating in space, suspended against a black background. Across its surface, the freshwater appears in blue, while the water we've lost is marked in red. And suddenly, as the years go by from 2002 to 2023, the planet becomes a deeper, deeper shade of that red.

We are losing our freshwater fast, and we are the reason. And this is where artistic creativity becomes an essential not a luxury. You don't just see the data, you feel it. It is the language that allows me to tackle those wicked problems and turn them into something we can grasp. We brought this project to COP28. There, we spoke with climate scientists, policymakers, Indigenous people who face water scarcity every day. Seeing their reactions in front of my artwork work gave me absolute certainty. Arts is the vital bridge, a missing link that has undeniable power to restore our lost connection.

Let's turn the conversation to your more recent work, which is to do with AI, which honestly to me is the least tangible and hardest for people to wrap their heads around. What was the point for you that you were like, okay, it's time to figure out how we get people to connect with their bodies, with their senses, to this invisible force in their lives?

For me, the reason why I actively started tackling the AI recently is because of the user interface. Before ChatGPT-4, the AI was still very difficult.

Yeah.

You have to have a proper coding knowledge. You have to have a proper experience so that you can train the model. But now everything is just at our fingertips. We just need to type it. So it removes all the barrier. And people start to using AI like a chatbot every day. So I thought that, well, something's going wrong. The technology is way much more complicated than any other technology of our time. But what is going on behind the clean user interface, we should talk about it. I felt a strong yearning to pull this intelligence into tangible forms. I wanted to make an overwhelming experience, something that you don't just look at, but something you inhabit with your body. We are at a threshold. To co-design our future with AI, we must ask, what is the shape of future AI? I built a physical answer to that question, and this is Light Architecture.

Picture yourself walking into a dark, circular room that represents The mind of the computer. Around you, 24 slender gold rods rise up from the floor, each with a light on top. Beams shoot across that floor, climbing the walls and reaching up to the ceiling, intersecting. And as the lights pulse, they form and break into patterns. It's almost as though they have their own language. This is Yoon's way of giving the activity inside an AI system a physical and beautifully arresting form.

In light architecture, AI takes a physical breath. These modules are no longer flat pixels, they are living neurons, and I call them neuropods. Here, you don't just watch a model, you stand inside the mind of a machine. I found my inspiration in human brain. Our brains have an incredible mechanism weaving data from cortex to deeper layers with the flexibility that AI cannot yet replicate. But it makes me wonder, with this incredible power inside our heads, are we genuinely training it? Or are we simply leaning on AI, paralyzed by the fear of being replaced by a machine, only to let our creativity and curiosity wither? Is that the future? Sometimes people find it scary. Some people find it very interesting. I don't give them an answer. It's rather having an opportunity to think about it. How do you want to design your life with AI?

I mean, it sounds like I hear your own feelings of—

Exactly.

Inflictedness. Because you used AI to make a piece of art. The artwork about AI, right?

Yes.

And so it sounds like you are curious about a symbiotic relationship with AI, but also cautious and skeptical and unsure.

It is so true. I mean, exactly. Like, a huge excitement, great anxiety, all kind of entangled inside of me. That's the reason why my artwork is also fluctuate. Positive, negative, you know, lighting and darkness. Because this is the technology we built. So we want to share that feeling together. And I want to believe that we still have an opportunity to make decisions, proper decisions, proper time. This is who I am. I'm an artist who builds bridges. I collaborate with scientists, I build systems, and I connect the physical and the virtual. My art is about building spaces where you can step inside and feel like you're in a different world. I do this because I believe one simple truth: that we are all deeply entangled.

That was artist Yiyun Kang. You can see her full talk at TED.com. Thank you so much for journeying through the senses with us on this episode. It was produced by Katie Montalvo. León, Harsha Nahada, and Rachael Faulkner-White, with help from Lucy Little. It was edited by Sana Azmashkinpour and me. Our production staff at NPR also includes Matthew Cloutier, Avery Keatley, Theo Guerin, and James Delahoussaye. Our executive producer is Irene Noguchi. Our audio engineer was Jimmy Keighley. Our theme music was written by Ramtin Arablouei. Our partners at TED are Sal Khan, Logan McLord-Davida, Ellen Walters, Roxanne Hailash, and Daniela Bellarezzo. I'm Minouche Zamorodi, and you have been listening to The TED Radio Hour from NPR.

The following message comes from NPR sponsor Henry Ford Health. Dr. Scott Dolcevsky, chairman of surgery and CEO of their Innovation Institute, shares how their partnership with NASA pushed him to think of new ways to apply medical technology.

What people don't realize is when you're in that spacesuit, it's a tiny spaceship, and that poses some challenges to the people in them. We were really worried about having a collapsed lung. How do you diagnose that? Well, here, if it happened at my ER, we'd do a chest X-ray. Well, we don't have an X-ray up there. Okay, well, we'd have a professional listen to the chest. Well, it's really noisy up in space because of fans and the power systems and things like that. Golly, that doesn't work. Would ultrasound work? Nobody had done that before. The ADAM project is Advanced Diagnostic Ultrasound in Microgravity. It's a simple 10-second solution. So now that's a capability on the space station. We do it regularly.

Learn more at henryford.com/scienceforthewin.