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Speaker 1: Hey, Daniel, I have a question about Noble prices. Well,

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Speaker 1: you know they aren't awarded until much later this year

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Speaker 1: or so, don't stay up late and wait by your phone. Really,

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Speaker 1: they don't give one for podcasts. No, and they also

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Speaker 1: don't give a banana prize. Well, my question is about

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Speaker 1: the Physics Nobel Prize. Well, I'm not staying up late

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Speaker 1: and waiting by the phone either. Well, my question is

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Speaker 1: whether it's given to some discovery that is deep or

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Speaker 1: a discovery that's useful to humanity. Why does it have

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Speaker 1: to be one or the other. Isn't deep knowledge also useful?

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Speaker 1: Have you found new trinos to be useful to humanity?

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Speaker 1: Not yet? Actually, I'm still waiting for aliens to teach

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Speaker 1: us how to use new trinos to get a safe tan. Yeah,

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Speaker 1: don't wait by the phone for that. Sweden call me, Jupiter,

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Speaker 1: call me? What does that even mean? If they're Aliens

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Speaker 1: and Jupiter? I want the Jovia Noble Prize for Best

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Speaker 1: Podcast Sidekick. You're not the sidekick. I'm what what I am?

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Speaker 1: John make cartoon is and the creator of PhD comments

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Speaker 1: I'm Daniel. I'm a particle physicist, and until a moment ago,

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Speaker 1: I thought I was the sidekick on this podcast, and

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Speaker 1: so welcome to our podcast, the award winning science and

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Speaker 1: physics podcast called Daniel and Jorge Explained the Universe. Remind

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Speaker 1: me which award we won. We won the award for

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Speaker 1: having no awards yet, the award for best podcast that

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Speaker 1: features only two sidekicks. We're sidekicking it here on our podcast.

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Speaker 1: But yeah, it's our podcast about physics and science and

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Speaker 1: astronomy and the universe and everything in between. Our podcast

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Speaker 1: in which we share with you the gorgeous, amazing mysteries

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Speaker 1: of the universe. We take you on a mental tour

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Speaker 1: to all the crazy stuff that's out there, that's in here,

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Speaker 1: the tiny stuff, the huge stuff, and we explain it

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Speaker 1: all to you in a way that we hope also

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Speaker 1: makes you chuckle, yeah, because you know, we hope to

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Speaker 1: open up your mind to the amazing and incredible things

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Speaker 1: that are happening right now and the far reaches of

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Speaker 1: the universe and the far corners of the Solar System.

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Speaker 1: But we also kind of want to open your eyes

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Speaker 1: to see you all of the amazing signs that's happening

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Speaker 1: all around you right now. Because one of the most

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Speaker 1: amazing things about physics is that the same laws of

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Speaker 1: physics operate on black holes and nebula and neutron stars

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Speaker 1: and you and me and everything in our world. This

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Speaker 1: is one of the most earth shattering revelations of physics

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Speaker 1: in the last few hundred years, that the physics of

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Speaker 1: the cosmos and the physics of the every day are

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Speaker 1: the same physics, which means that we can discover the

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Speaker 1: secrets of the universe just by doing experiments in our laboratory. Yeah,

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Speaker 1: it's all the same being trapped in a black hole

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Speaker 1: or being trapped in your apartment for an indefinite amount

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Speaker 1: of time. It's all the same. You can do physics anywhere.

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Speaker 1: They're crushing in different ways. But it also means that

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Speaker 1: we can look around us and find amazing crazy stuff

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Speaker 1: that reveals the grits of the universe. Like quantum mechanics

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Speaker 1: was not discovered inside a black hole. It was found

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Speaker 1: just by shooting photons that weird kinds of metal. And

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Speaker 1: so today we'll be talking about an invention. Dad, I

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Speaker 1: would argue maybe is one of the most commonplace or

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Speaker 1: most prevalent technologies out there in human technology human kind. Right,

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Speaker 1: are you talking about the wheel fire the hoverboard, and

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Speaker 1: I was hoping for the hoverboard. Hasn't had that happened yet, Daniel, No,

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Speaker 1: it is not. But I'm sure somebody accidentally ordered a

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Speaker 1: hoverboard on Amazon and got something else. You know. Well,

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Speaker 1: it's a technology that I think basically almost every human

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Speaker 1: looks at on a daily basis, maybe even an hourly basis.

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Speaker 1: Now you have me at the edge of my seat.

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Speaker 1: What are we talking about today? What do you mean?

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Speaker 1: I thought you knew what we were talking about today.

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Speaker 1: I'm the sidekick here. Remember you're in charge. Oh I see,

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Speaker 1: I see. Well, it's in our phones, you know, everyone

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Speaker 1: looks at their phone every couple of minutes. It's on

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Speaker 1: our computer screens and our televisions, which I'm sure a

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Speaker 1: lot of people are watching a lot of these days.

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Speaker 1: So it illuminates everything you're talking about. My sheer genius, right,

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Speaker 1: my brilliance about Netflix. I'm just kidding. Well, it's I

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Speaker 1: just figured out it's on the title of our podcast.

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Speaker 1: So I'm guessing that people will already know by the

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Speaker 1: time they click that's right. I hope they haven't been misled.

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Speaker 1: That's right. We'll lead him to the light. That's right,

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Speaker 1: So to have the podcast, we'll be talking about l

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Speaker 1: E d S. How do elds work, what are the

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Speaker 1: physics of it? And why did somebody win a Nobel

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Speaker 1: Prize for inventing a particular color of it? That's right,

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Speaker 1: We have physics Nobel Prizes for things like understanding quantum

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Speaker 1: mechanics and figuring out what the basic particles are, or

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Speaker 1: for you know, an observation of gravitational ways. Things really

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Speaker 1: reveal the fundamental fabric and nature of the universe. And

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Speaker 1: then we have Nobel Prizes for the invention of the

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Speaker 1: blue led blue eled, not the red led. That one

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Speaker 1: did not win. It was blued, Nobel's favorite color. Not

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Speaker 1: at all, not at all. And so today we wanted

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Speaker 1: to dive into, like what are the physics of L

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Speaker 1: E d S. Is it's really worth a Nobel Prize?

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Speaker 1: What are the sort of obstacles that they had to

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Speaker 1: leap over in order to make this thing work? And

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Speaker 1: what physics did they have to solve along the way.

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Speaker 1: What does it reveal about the nature of our universe

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Speaker 1: that we can now make L d's globe blues? So

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Speaker 1: what do you think about my idea that it's maybe

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Speaker 1: one of the most prevailing technologies out there, you mean

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Speaker 1: lights in general, or LED specifically, L E D specifically,

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Speaker 1: you know, because they're they're basically in every phone, and

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Speaker 1: there's billions of phones out there, and it's on every

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Speaker 1: computer screen now in TV screen, most of the TV

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Speaker 1: screens have them. I would say it's up there along

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Speaker 1: with a concrete and toilet paper as the current most

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Speaker 1: important technology. Yeah. You know, people have been stockpiling L

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Speaker 1: e d s ever since the coronavirus came out, you know,

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Speaker 1: just in case, yeah, you know, just in case we

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Speaker 1: run out of lights. I think you're right. Just had

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Speaker 1: a really big impact on everyday life. You see them

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Speaker 1: in screens, you see them in lights, you see them

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Speaker 1: on trucks, you see them everywhere now. Yeah. Yeah, So

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Speaker 1: it's a pretty important technology that's all around us, that

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Speaker 1: is hitting our eyeballs all of the time. But as usually,

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Speaker 1: we were wondering how many people out there know how

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Speaker 1: L e d s work or what it even stands for.

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Speaker 1: L E ED. So, as usual, Daniel went out into

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Speaker 1: the world and ask people if they do how an

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Speaker 1: LED works. That's right, and these questions actually pre date

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Speaker 1: the coronavirus pandemic and so these are historical records of

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Speaker 1: in person interviews back when that was still possible. Really, Oh,

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Speaker 1: this is an actual on the street. These are from

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Speaker 1: the archive. We haven't had a chance to pull this

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Speaker 1: episode out yet. I see. Do you think people's opinions

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Speaker 1: about l E d S would have changed by now?

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Speaker 1: While people are spending more time inside under the life

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Speaker 1: of a deeper relationship with L E d S. Now,

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Speaker 1: maybe hypnotizes a little bit more since Yeah, well you know,

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Speaker 1: people are looking at more screens and so they have

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Speaker 1: hopefully more affection for L D. Yeah. So think about

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Speaker 1: it for a second. If someone asked you how an

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Speaker 1: LED works, would you know what to answer. Here's what

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Speaker 1: people had to say. No, but I just know it's

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Speaker 1: a better life. Part of me really wants you to

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Speaker 1: say electricity, but uh, isn't it No, that's fluorescence. Remind

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Speaker 1: I was gonna say gas, but let's just fluorescence light. Yeah,

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Speaker 1: I'm going to assume it's due to a residents frequency

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Speaker 1: within within the LED. I'm not sure. Essentially, it's just

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Speaker 1: a PM junction. Um one side has holes in side

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Speaker 1: has an accessible electrons, especially transitions in the state of

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Speaker 1: the PM junction. Really slight. So yeah, oh shoot, um, honestly,

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Speaker 1: I don't know. I literally don't know. Kind of yeah, yeah,

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Speaker 1: I know, um excited Adams, but I forgot like which

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Speaker 1: Adam like maybe alien They excited to higher state energy

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Speaker 1: state and wave falls generated energy. But yeah, that's kind

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Speaker 1: of isn't that. Florescen no similar, but fluorescence like much

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Speaker 1: weaker energy. So what do you think of these responses?

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Speaker 1: Pretty good? I feel like they fall in live with

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Speaker 1: how I think about l d S, which is that

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Speaker 1: I don't know much about him. Yeah, I was a

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Speaker 1: little surprised. Some people had no idea. Some people thought

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Speaker 1: they understood it, but we're actually talking about a completely

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Speaker 1: different type of light generation that's fluorescence. People got them

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Speaker 1: confused with fluorescent, Like yeah, yeah, In turns out there's

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Speaker 1: lots of different ways to make light. You know, you

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Speaker 1: incandescent light, we have fluorescent lights, and then we have

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Speaker 1: led lights, and they all operate on really different physical principles. Yeah,

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Speaker 1: because maybe maybe people have got them confused, because I

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Speaker 1: feel like fluorescent lights, I know, they've been around for

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Speaker 1: a long time, you know, like neon signs and things

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Speaker 1: like that, and fluorescent bulbs, but they sort of made

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Speaker 1: it into people's homes more recently, but then right away

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Speaker 1: elid sort of came about and then totally replaced them. Yeah, well,

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Speaker 1: fluorescent lights have been around for quite a long time,

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Speaker 1: but yeah, they didn't make it into people's homes until

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Speaker 1: recently with the compact fluorescence. But there's actually sort of

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Speaker 1: a fascinating legal drama aout florescent lights because they were

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Speaker 1: first developed pretty soon after incandescent lights, but then General

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Speaker 1: Electric bought up all the patents and prevented anybody from

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Speaker 1: developing them or using them, and basically kept fluorescent lights

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Speaker 1: out of the market for decades just because they also

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Speaker 1: owned the patents for incandescent lights. So it's sort of

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Speaker 1: a legal political drama that we probably won't even get

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Speaker 1: into today. They're like fluorescence that that works with gas,

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Speaker 1: it's not electric. It's on brand with us, so we'll

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Speaker 1: just sit in it. Yeah, they just sort of bought

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Speaker 1: it up and sat on it as a dangerous technology

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Speaker 1: that they thought would sort of endanger their business. Well,

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Speaker 1: let's get into how LEDs work, but first let's maybe

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Speaker 1: talk about how some of the other lights that people

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Speaker 1: are familiar with work. So take us back, Daniel, how

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Speaker 1: does it torch work. You know, that's a really awesome

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Speaker 1: question actually, like what is fire and how does it work?

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Speaker 1: And I want to do a whole podcast episode, Um,

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Speaker 1: what is fire and what is the thing you're seeing

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Speaker 1: that's glowing? And remember it's it's gonna be totally lit.

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Speaker 1: M We're gonna brighten your life with that one. And

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Speaker 1: remember on our live streams, somebody asked about that whether

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Speaker 1: fire can have a shadow, which is a totally awesome question.

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Speaker 1: But I think the first light that we should talk

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Speaker 1: about is incandescent lights. And these are the ones that

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Speaker 1: Edison invented, you know, the ones that people have had

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Speaker 1: in their homes until very recently. It has a little

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Speaker 1: filament in it that glows and eventually it breaks, right. Yeah,

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Speaker 1: basically what people think of when they think of a

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Speaker 1: light bulb, like a round thing with a little wire

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Speaker 1: through the middle. Yeah, that's your classic light bulb. And

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Speaker 1: all the technologies that we're gonna talk about today operate

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Speaker 1: under the same essential goal, which is turned electricity into photons.

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Speaker 1: Do you think when Edison had the idea for the

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Speaker 1: light bulb, do you think he had a light bulb

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Speaker 1: over his head? Like, was that the only time in

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Speaker 1: history when like somebody was actually thinking of a light bulb,

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Speaker 1: when they had an idea. Yeah, that's where it comes from, right,

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Speaker 1: that was the first great idea, That was the first

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Speaker 1: idea worthy of having a light bulb over your head. Technically,

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Speaker 1: that's true. Yeah, And so the idea for incandescent lights

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Speaker 1: is to find some material where you can deposit the

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Speaker 1: energy from your electrons and it will give off light.

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Speaker 1: All right, So every one of these strategies you want

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Speaker 1: to turn fast moving electrons into shooting off photon photons

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Speaker 1: to the surrounding areas. Okay, so how do incandescent lights work?

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Speaker 1: How do light bulbs work? Regularly? The amazing thing about

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Speaker 1: light bulbs that people probably don't understand is that they

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Speaker 1: glow even when they're off. What. Yeah, everything glows. It's

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Speaker 1: called black body radiation. Everything in the universe gives off photons,

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Speaker 1: gives off radiation, even if it's totally black, even if

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Speaker 1: it's a black hole, daddy. Well, technically, yes, black holes

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Speaker 1: do give up a radiation all right, Yeah, that's true. Correct,

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Speaker 1: Even black holes have a temperature. Right, Everything in the

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Speaker 1: universe that's not an absolute zero glows at some spectrum. Now,

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Speaker 1: usually you don't see it because it's invisible. It glows

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Speaker 1: very very very long wavelengths, very low frequencies, and so

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Speaker 1: you don't see it. So but this is why, for example,

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Speaker 1: you know infrared telescopes like the James web Space telescope

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Speaker 1: that looks for infrared light. It sees a lot out

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Speaker 1: of noise that you don't even see and have to

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Speaker 1: keep it cold a like negative fifty degrees or whatever.

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Speaker 1: So everything in the universe is already glow, but it's

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Speaker 1: not so useful, right, What you want is something that

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Speaker 1: glows with light that you can see a lot. Right. Oh,

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Speaker 1: I see black body radiation is in the infrared. It's

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Speaker 1: much lower than the infrared. Yet most black body radiation,

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Speaker 1: like the cosmic Marcrowave background radiation, is black body radiation

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Speaker 1: from that initial plasma of the universe. And is it

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Speaker 1: like you know, three degrees kelvin. It's a very very

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Speaker 1: long wavelength. But what about something that's at zero degreek kelvin,

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Speaker 1: like absolute zero? Would that still glow? You know, something

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Speaker 1: that absolute zero can't glow. But there is nothing in

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Speaker 1: the universe at absolute zero. So if you're like at

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Speaker 1: point oh one degrees kelvin, from absolute zero, you would

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Speaker 1: be glowing a little bit exactly. And that's why the

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Speaker 1: black hole stuff is actually quite fascinating because when Stephen

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Speaker 1: Hawking developed his ideas of black holes having a temperature,

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Speaker 1: that automatically suggests that black holes should radiate, because like

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Speaker 1: everything else that has a temperature, should radiat And that's

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Speaker 1: why Hawkings results are sort of black hole thermo dynamics,

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Speaker 1: because he's thinking about the temperature of black holes and

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Speaker 1: how that connects to how they radiate. All right, so

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Speaker 1: everything glows into infrared, So how do we get things

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Speaker 1: to glow in the in the visible light the white

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Speaker 1: light spectrum. Yes, so the spectrum in which you glow

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Speaker 1: depends on your temperature. So really cold stuff glows in

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Speaker 1: the infrared. If you heat something up, then its emissions

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Speaker 1: move into the visible spectrum. So you want to make

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Speaker 1: your filament glow in the visible light instead of in

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Speaker 1: the infrared light. Than what you do is you make

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Speaker 1: it hot, hotter and hotter. It turns the light from

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Speaker 1: it not just glows more, but it changes color. It

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Speaker 1: changes color. And that's why for example, you heat up

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Speaker 1: metal right and you see it glows blue, it glows red,

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Speaker 1: It glows white, for example, and the temperature of the

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Speaker 1: metal determines the frequency at which it's glowing, right, Like

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Speaker 1: white hot and red hot are different temperatures of metal R.

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Speaker 1: And so this is a basic principle. And what's going

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Speaker 1: on in the physics sense, like what's going on with

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Speaker 1: the electrons on the atoms, why is it changing color?

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Speaker 1: And how is it giving off the light. So it's

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Speaker 1: always a good idea to try to think about stuff microscopically.

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Speaker 1: And that's not just because I'm a particle physicist that

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Speaker 1: I think we should always be thinking about the tiny stuff.

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Speaker 1: I think it really does lead to some inside And

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Speaker 1: so what's happening microscopically when you heat something up is

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Speaker 1: that the electrons inside of the particles inside it have

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Speaker 1: more ways to move. They're wiggling more, they're bouncing more.

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Speaker 1: So there's just a lot more energy there. Now. The

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Speaker 1: way something glows is when something moves from a higher

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Speaker 1: energy level to a lower energy level. I mean, like

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Speaker 1: the atoms in a decay or sort of degrade a

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Speaker 1: little bit or chill out. And when they do that,

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Speaker 1: they admit a hotel. Yeah, they're excited. They have some

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Speaker 1: energy stored in them, and that energy comes from you know,

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Speaker 1: whatever you did to heat up this material. Right, Heat

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Speaker 1: means internal energy stored in the motion of these objects,

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Speaker 1: and we had a whole podcast about what temperature means

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Speaker 1: and it turns out to be very confusing and amazing,

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Speaker 1: like everything else in the universe. But the way to

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Speaker 1: think about microscopically is that these atoms are excited. Either

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Speaker 1: the electrons that are whizzing around them have gone up

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Speaker 1: one ladder in the energy level, or two ladders or

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Speaker 1: three ladders, or maybe they're vibrating in new ways or

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Speaker 1: rotating in new ways. These are all ways that they

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Speaker 1: can store energy. The electrons are that are the atoms.

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Speaker 1: The electrons can move up energy levels, but the atoms

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Speaker 1: also they can vibrate. Remember a lot of these are

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Speaker 1: in bonds, right. Metals are not just free floating gases.

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Speaker 1: These lattices of things tied together and they're like you

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Speaker 1: can imagine little springs between them, and then you can

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Speaker 1: imagine those things vibrating and vibrating in different ways. They

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Speaker 1: have different modes, all right. So they're excited and so

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Speaker 1: they they're giving off energy and then they relax. Because

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Speaker 1: things in the universe don't like to be excited. They

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Speaker 1: like to spread out their energy, and that's why things

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Speaker 1: emit energy because entropy, right, energy in the universe tends

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Speaker 1: to diffuse, and so if you have it concentrated in

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Speaker 1: one little mode, like one little electron has jumped up

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Speaker 1: three energy levels, it will decay. You'll give that energy off.

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Speaker 1: And the way it does that is by shooting off

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Speaker 1: a photon. And so the more you heat up something up,

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Speaker 1: the more you make all the atoms more excited, the

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Speaker 1: more you know photons that are going to come off

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Speaker 1: of this excitement exactly, and then the higher the energy

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Speaker 1: of those gaps, So an electron can get pushed up

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Speaker 1: several levels up that ladder, and then it can jump

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Speaker 1: down five levels, and so then the photon has more energy,

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Speaker 1: which corresponds to a higher frequency. So that's how, for example,

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Speaker 1: hot objects can emit in the visible spectrum instead of

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Speaker 1: just at the very very low energy levels. So the

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Speaker 1: light that they emit has more energy, which is what

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Speaker 1: higher frequency means, which is what visible light means, or

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Speaker 1: invisible light has more energy per photon than infrared light.

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Speaker 1: But I think it also has to be certain kinds

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Speaker 1: of materials, right, like when I boil water, it doesn't

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Speaker 1: start to blow. I mean it starts to glow in

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Speaker 1: the infrared, but not in the visible light spectrum. That's

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Speaker 1: an awesome question. How hot would you have to make

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Speaker 1: water in order to make it glow? I don't think

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Speaker 1: answer to that. That's a cool question. But you're right, Yeah,

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Speaker 1: everything glows at some level, but not everything can be

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Speaker 1: easily made to glow in the visible because I guess

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Speaker 1: it will melt or burn or boil, yeah, exactly, something

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Speaker 1: else will happened to it turn into vapor. And so

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Speaker 1: that that's how light bulbs work. It's that they have

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Speaker 1: a little thin wire of metal that you heat up

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Speaker 1: and then that gives us the light. That's right. And

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Speaker 1: the way you heat it up is that you send

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Speaker 1: current through it, right, You send electricity through it. And

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Speaker 1: most of these metals are resistors, meaning that they are

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Speaker 1: not perfect conductors. So the electrons as they're trying to

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Speaker 1: go through the metal are getting bounced into atoms, right,

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Speaker 1: and those atoms are stealing their energy. And this is

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Speaker 1: what heats up something when electricity passes through it. Like

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Speaker 1: you know that block that you used to charge your laptop.

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Speaker 1: Have you've been charging it for a while, it heats up, right,

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Speaker 1: that's using. That's inefficient. It's using. It's stealing the electricity

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Speaker 1: from those electrons in order to heat up that block.

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Speaker 1: This is how you heat up the filament of tungsten.

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Speaker 1: As you pass all this electricity through it, that heats

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Speaker 1: it up and that makes it glow. Yeah, that's a

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Speaker 1: little wire inside of the traditional light bulb and white tungsten.

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Speaker 1: Is it a special kind of metal? They can heat

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Speaker 1: up a lot without melting. Yeah, tungsten just sort of

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Speaker 1: lasts a long time. But these things are really very

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Speaker 1: very inefficient. Like it's not a very direct way to

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Speaker 1: get energy into photons. Right, You're just heating this thing

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Speaker 1: up and it's glowing somewhat in the visible but not

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Speaker 1: always invisible, and a lot of the energy is just lost.

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Speaker 1: A lot of the energy goes into the infrared, which

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Speaker 1: is useless to us. Yeah, it just goes into making

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Speaker 1: this thing hot, right, and not all the heat gets

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Speaker 1: turned into visible light, and so only something like five

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Speaker 1: of the energy that you put into a light bulb

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Speaker 1: gets turned into light. Superficient, not super efficient and also

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Speaker 1: kind of fragile, like you're baking this thing every single time,

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Speaker 1: So it gets hot and then it gets cold, and

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Speaker 1: gets hot and then it gets cold, and you know that,

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Speaker 1: like that creates a lot of mechanical stress, which is

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Speaker 1: why these filaments, which are already very very thin, don't

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Speaker 1: last for that long. So your typical incandescent classic light

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Speaker 1: bulb only works for about a thousand hours. Well, they're

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Speaker 1: making a comeback, you know, and like hip her restaurants

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Speaker 1: and stuff, everyone's going for the incandescent bulbs. Yeah. Well,

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Speaker 1: the positive thing about incandescent bulbs is to have a

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Speaker 1: very nice glow, Like it feels like sort of a

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Speaker 1: natural light. You know that the process that produces this

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Speaker 1: light gives you a spread, right, not just one color.

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Speaker 1: It's not like a laser beam in your eye. It's

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Speaker 1: a nice spread of warm white light. And so a

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Speaker 1: lot of people like that. It's sort of more similar

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Speaker 1: to sunlight than some of the other technologies we're gonna

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Speaker 1: talk about, saying, all right, let's get into some of

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Speaker 1: these other technologies like l d s, like fluorescent light bulbs,

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Speaker 1: but first let's take a quick break. All right, there,

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Speaker 1: we're talking about how LEDs work and specifically how lights

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Speaker 1: work in general, and so we're going down the list

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Speaker 1: of technologies, and so we talked about incandescent bulbs, which

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Speaker 1: I'm guessing maybe my kids will never have to know

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Speaker 1: how they work technically because everything is sort of moved on.

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Speaker 1: But the next one in the history of light is

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Speaker 1: the fluorescent light bulb. So you were saying these were

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Speaker 1: invented out around the same time as the incandescent light bulb,

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Speaker 1: but they worked on a totally different physics. Yeah, the

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Speaker 1: physics is different. The idea here is to use excited gas,

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Speaker 1: and you know, we talked about in the late eighteen

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Speaker 1: hundreds of people were making vacuum tubes and you know,

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Speaker 1: passing currents through it and seeing glows, and that's actually

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Speaker 1: one of the things that lead to the discovery of

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Speaker 1: the electron, right J. J. Thompson discovered the electron by

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Speaker 1: playing with these sort of evacuated tubes and seeing how

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Speaker 1: the gas inside them glows. But then people were playing

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Speaker 1: with other kinds of things and discovered that if you

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Speaker 1: pass a current through a tube that has gas in it,

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Speaker 1: you can make the gas glow. And the physics here

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Speaker 1: is pretty similar to the physics of incandescent lights, except

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Speaker 1: that you're making a gas glow. Instead of making like

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Speaker 1: a piece of metal glow, I see, instead of a

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Speaker 1: little wire, it's like a tube of gas and you

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Speaker 1: can excite the electrons in that gas. They go up

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Speaker 1: an energy level and then they jump back down and

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Speaker 1: they give off a photon. And I think last time

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Speaker 1: we talked about these, it was it's sort of related

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Speaker 1: to lightning the way kind of it's it's almost like

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Speaker 1: you're creating a little bit of lightning in a bottle. Yeah,

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Speaker 1: it's lightning in a bottle, and it's a little bit

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Speaker 1: of plasma, right. You In order to pass electricity through

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Speaker 1: a gas, you have to turn it into ions. You

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Speaker 1: have to tear apart the positive and the negative that

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Speaker 1: usually the gas is made out of and make an

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Speaker 1: ion channel. And you know this sounds like Star Trek

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Speaker 1: or whatever, but you're literally making a tube of electrically

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Speaker 1: charged gas. It's like a gaseous wire sort of cool.

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Speaker 1: It's like a gas that conducts electricity, right, and so

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Speaker 1: you're tearing it apart just by creating this electric field

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Speaker 1: from one side to the other and then passing that

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Speaker 1: energy through and it excites the gas. It makes the

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Speaker 1: gas like the atoms of the gas inside are now

427
00:21:34,040 --> 00:21:37,040
Speaker 1: giving off there like absorbing these electrons that are going through,

428
00:21:37,119 --> 00:21:39,000
Speaker 1: and then they give him off as photon. That's right.

429
00:21:39,000 --> 00:21:41,840
Speaker 1: The microphysics of what's happening is that these electrons, the

430
00:21:41,920 --> 00:21:45,200
Speaker 1: current that's passing through will sometimes bump into an electron

431
00:21:45,359 --> 00:21:48,240
Speaker 1: in the gas atom and bump it up a few

432
00:21:48,320 --> 00:21:50,639
Speaker 1: energy levels and then it will fall back down. And

433
00:21:50,680 --> 00:21:52,959
Speaker 1: when it does that, it gives off a photon. So

434
00:21:53,000 --> 00:21:56,600
Speaker 1: you're turning the kinetic energy of some initial electron into

435
00:21:56,600 --> 00:22:00,240
Speaker 1: an excited state of the atomic electron, which then it's

436
00:22:00,280 --> 00:22:02,400
Speaker 1: a photon. So that's how you get an energy from

437
00:22:02,400 --> 00:22:04,560
Speaker 1: the electron into a photon. And it's kind of a

438
00:22:04,600 --> 00:22:08,119
Speaker 1: binary process, right, Like it's hard to dim a fluorescent

439
00:22:08,320 --> 00:22:11,120
Speaker 1: light bulb, right, Like a little regular ballb you can

440
00:22:11,119 --> 00:22:13,320
Speaker 1: do that, but a fluorescent you know, it's either on

441
00:22:13,359 --> 00:22:15,520
Speaker 1: and offer and if it's sort of on the edge,

442
00:22:15,520 --> 00:22:17,639
Speaker 1: you'll blink and kind of give you ice cream. That's right.

443
00:22:17,680 --> 00:22:19,760
Speaker 1: Because you need to create this plasma, you need to

444
00:22:19,800 --> 00:22:22,199
Speaker 1: like ramp it up to a high enough voltage so

445
00:22:22,200 --> 00:22:24,600
Speaker 1: that you can create this ion channel and the whole

446
00:22:24,640 --> 00:22:27,080
Speaker 1: thing starts up. It's almost like starting up a little

447
00:22:27,160 --> 00:22:32,080
Speaker 1: fusion reactor. Inside suddenly it Fluorescent light bulbs are way cool.

448
00:22:32,400 --> 00:22:35,280
Speaker 1: They're lightning in a bottle and fusion bombs in a tube. Yeah,

449
00:22:35,320 --> 00:22:36,920
Speaker 1: And the cool thing about them is that they're a

450
00:22:36,960 --> 00:22:40,440
Speaker 1: lot more efficient doing this with gas. Like a mercury vapor,

451
00:22:40,480 --> 00:22:43,840
Speaker 1: which is what's typically used, is something like twenty efficient

452
00:22:43,880 --> 00:22:47,080
Speaker 1: instead of like the five percent of your incandescent light bulb.

453
00:22:47,160 --> 00:22:50,960
Speaker 1: Where does the other scent efficiency go into heat as well?

454
00:22:51,000 --> 00:22:53,879
Speaker 1: But they don't. They don't get as that that's exactly right.

455
00:22:53,920 --> 00:22:56,520
Speaker 1: They don't get as hot, which is why they're more efficient. Right,

456
00:22:56,840 --> 00:22:59,560
Speaker 1: some more the energy goes into creating light unless of

457
00:22:59,600 --> 00:23:02,320
Speaker 1: it goes into like heating up the actual apparatus. So

458
00:23:02,560 --> 00:23:05,440
Speaker 1: I think that all makes sense. One interesting facet which

459
00:23:05,440 --> 00:23:07,720
Speaker 1: I thought was cool was that the best thing to

460
00:23:07,880 --> 00:23:10,720
Speaker 1: use to make this light is mercury vapor because you

461
00:23:10,760 --> 00:23:13,760
Speaker 1: don't need really high voltage and it's it's one of

462
00:23:13,800 --> 00:23:15,800
Speaker 1: the most efficient ways to do it. But mercury is

463
00:23:15,840 --> 00:23:19,920
Speaker 1: like super poisonous, which is which makes it like it's

464
00:23:19,920 --> 00:23:23,719
Speaker 1: a bad idea. Also, mercury gives off light, it's not visible,

465
00:23:23,840 --> 00:23:27,360
Speaker 1: it gives off ultra violet light. Oh my goodness, poisons

466
00:23:27,400 --> 00:23:30,000
Speaker 1: you and gives you cancer at the same time. No,

467
00:23:30,200 --> 00:23:32,120
Speaker 1: but that's why a lot of these fluorescent light bulbs

468
00:23:32,160 --> 00:23:35,560
Speaker 1: are not clear. They're frosted because the inner side of

469
00:23:35,600 --> 00:23:40,440
Speaker 1: the glass contains another material which absorbs the ultra violet light,

470
00:23:41,000 --> 00:23:42,960
Speaker 1: uses some of the energy, and then gives off light

471
00:23:43,040 --> 00:23:45,400
Speaker 1: in the visible So it's like a two step process.

472
00:23:45,680 --> 00:23:49,080
Speaker 1: The mercury vapor gives off UV photons which are then

473
00:23:49,160 --> 00:23:53,080
Speaker 1: like stepped down into the visible light by some phosphorescent

474
00:23:53,119 --> 00:23:56,600
Speaker 1: coating inside the bowl. It's a lot to it. Yeah,

475
00:23:56,640 --> 00:23:59,040
Speaker 1: it's a complicated thing, and you know, you have to

476
00:23:59,040 --> 00:24:01,399
Speaker 1: create this plasma. And that's why florescent light bulbs until

477
00:24:01,440 --> 00:24:04,280
Speaker 1: recently not as commonly used in the home. They're more

478
00:24:04,280 --> 00:24:07,000
Speaker 1: expensive and more complicated, but there are a lot more

479
00:24:07,000 --> 00:24:11,680
Speaker 1: efficient instead of five and they work for like ten

480
00:24:11,800 --> 00:24:14,560
Speaker 1: thousand hours instead of a thousand hours. And the light

481
00:24:14,680 --> 00:24:18,160
Speaker 1: is kind of different too. It's it's wider, generally, it's wider. Yeah,

482
00:24:18,200 --> 00:24:20,040
Speaker 1: and it kind of drives me bonkers, Like I don't

483
00:24:20,080 --> 00:24:21,760
Speaker 1: like the light from fluorescent light bulbs. It makes me

484
00:24:21,800 --> 00:24:24,359
Speaker 1: feel like I'm you know, in a target or in

485
00:24:24,480 --> 00:24:30,480
Speaker 1: like an alien autopsy examination room. Target and alien autopsy

486
00:24:30,560 --> 00:24:34,440
Speaker 1: that's where your mind goes it's worse worst case scenarios. Well, actually,

487
00:24:34,480 --> 00:24:36,000
Speaker 1: now that I think about it, I love to be

488
00:24:36,080 --> 00:24:39,719
Speaker 1: in an alien autopsy or target for that, to be honest.

489
00:24:40,840 --> 00:24:42,800
Speaker 1: It's just that I don't know why the lighting in

490
00:24:42,960 --> 00:24:46,879
Speaker 1: alien autopsy scenes in science fiction is always so terrible,

491
00:24:46,880 --> 00:24:50,080
Speaker 1: Like why do they always use the horrible fluorescent flickering lights?

492
00:24:50,280 --> 00:24:52,600
Speaker 1: I see, Well, it's just so that the green comes

493
00:24:52,600 --> 00:24:54,840
Speaker 1: out of their skin more, you know, makes this there's

494
00:24:55,119 --> 00:24:58,040
Speaker 1: green skin seemed lovelier. I see. The aliens agent insisted

495
00:24:58,240 --> 00:25:01,840
Speaker 1: that they have it that way, is in their contract. Alright, well,

496
00:25:02,040 --> 00:25:11,320
Speaker 1: brown eminem's and fluorescent lights, that's right. And I didn't

497
00:25:11,320 --> 00:25:13,240
Speaker 1: think that would make you laugh so much, Daniel. I

498
00:25:13,240 --> 00:25:16,720
Speaker 1: don't think aliens are so vain alright, alright, well hopefully not.

499
00:25:17,119 --> 00:25:20,480
Speaker 1: But yeah, so that's incandescent and fluorescent lights. And so

500
00:25:20,560 --> 00:25:22,679
Speaker 1: let's get into the topic of the podcast, which is

501
00:25:22,680 --> 00:25:26,320
Speaker 1: how LED lights work. And these are pretty pretty recent.

502
00:25:26,320 --> 00:25:28,520
Speaker 1: I feel like in the last ten years they've become

503
00:25:28,560 --> 00:25:32,160
Speaker 1: more popular, and they're also sort of everywhere right there,

504
00:25:32,160 --> 00:25:34,600
Speaker 1: in phones, they're in TVs or pretty much every kind

505
00:25:34,640 --> 00:25:37,000
Speaker 1: of screen, even on people's watches now have L E

506
00:25:37,080 --> 00:25:39,399
Speaker 1: D s and so first of all, Daniel, what is

507
00:25:39,560 --> 00:25:43,159
Speaker 1: l ED stand for. It stands for light emitting diode.

508
00:25:43,720 --> 00:25:47,560
Speaker 1: Light emitting is obvious, right, giving off light and diode

509
00:25:47,720 --> 00:25:50,960
Speaker 1: is this little physical thing that was invented in the

510
00:25:51,000 --> 00:25:54,360
Speaker 1: fifties and sixties that's made out of semiconductors. And that's

511
00:25:54,359 --> 00:25:57,840
Speaker 1: really the core idea here is that instead of using

512
00:25:57,960 --> 00:26:00,920
Speaker 1: a hot little tube of metal or a hot tube

513
00:26:00,920 --> 00:26:02,880
Speaker 1: of gas, let's see if we can build this thing

514
00:26:02,920 --> 00:26:06,800
Speaker 1: out of semiconductors. And semiconductors are what computer chips are

515
00:26:06,840 --> 00:26:08,880
Speaker 1: made out of, right, I mean, that's what computers are

516
00:26:09,200 --> 00:26:11,560
Speaker 1: made out of. So this is kind of like they

517
00:26:11,640 --> 00:26:14,680
Speaker 1: adapted that technology or they figured out they can also

518
00:26:14,760 --> 00:26:17,000
Speaker 1: use it to midlight, they can also use to emdlight.

519
00:26:17,040 --> 00:26:21,199
Speaker 1: And you're write, semiconductors are incredible also the basis of transistors,

520
00:26:21,400 --> 00:26:23,680
Speaker 1: which is how we build computer chips. One of the

521
00:26:23,720 --> 00:26:26,120
Speaker 1: cool things about semiconductors is that we can print them

522
00:26:26,160 --> 00:26:29,399
Speaker 1: really Finally, we can construct super tiny circuits that have

523
00:26:29,480 --> 00:26:32,959
Speaker 1: really specific semiconductors using lithography, and that's how we make

524
00:26:33,000 --> 00:26:35,320
Speaker 1: computer chips so small, and we can make l ED

525
00:26:35,480 --> 00:26:38,440
Speaker 1: s really small. But first maybe we should talk about

526
00:26:38,440 --> 00:26:41,480
Speaker 1: like what a semiconductor is like, it's not somebody who's

527
00:26:41,520 --> 00:26:44,760
Speaker 1: like driving a semi for example, someone who's dead driving

528
00:26:44,760 --> 00:26:48,920
Speaker 1: with one eye closed, or conducting an orchestra, but only

529
00:26:48,960 --> 00:26:51,919
Speaker 1: half the time, yeah, looking at their phone. And so

530
00:26:52,040 --> 00:26:54,359
Speaker 1: to understand semiconductor you have to understand where it falls

531
00:26:54,359 --> 00:26:57,720
Speaker 1: sort of between other objects like an insulator and a conductor.

532
00:26:57,800 --> 00:27:01,480
Speaker 1: It's basically like a conductor that you can control right,

533
00:27:01,560 --> 00:27:04,000
Speaker 1: like it's a resistor, but you can also shut it

534
00:27:04,040 --> 00:27:06,200
Speaker 1: off if you give it a different sign sort of. Yeah,

535
00:27:06,240 --> 00:27:08,199
Speaker 1: I think if it's sort of like a combination between

536
00:27:08,200 --> 00:27:12,400
Speaker 1: an insulator and a conductor, because in an insulator, electrons

537
00:27:12,520 --> 00:27:15,400
Speaker 1: cannot jump between atoms, like one atom has its electrons

538
00:27:15,400 --> 00:27:17,679
Speaker 1: and the other one has its electrons, and electrons just

539
00:27:17,840 --> 00:27:20,920
Speaker 1: stay in their atom. They have a little localized the

540
00:27:20,960 --> 00:27:23,600
Speaker 1: neighborhood that they hang out in. But in a conductor,

541
00:27:23,600 --> 00:27:27,119
Speaker 1: the electrons flow freely, like they don't necessarily have an assignment.

542
00:27:27,160 --> 00:27:28,760
Speaker 1: They don't have like a home address. They just sort

543
00:27:28,800 --> 00:27:31,719
Speaker 1: of like move around between atoms. It doesn't take much

544
00:27:31,800 --> 00:27:34,080
Speaker 1: energy to go from one atom to the next. There's

545
00:27:34,080 --> 00:27:38,080
Speaker 1: no barrier there. It insulates, you can't conduct electricity. Yeah,

546
00:27:38,119 --> 00:27:41,240
Speaker 1: so insulators electrons can't jump between atoms, and a conductor,

547
00:27:41,240 --> 00:27:44,879
Speaker 1: electrons just flow very easily between atoms. Now in the

548
00:27:44,920 --> 00:27:48,679
Speaker 1: semiconductor has both, right, it has there's a flow zone

549
00:27:49,000 --> 00:27:51,520
Speaker 1: and a no flow zone. So if you have enough energy,

550
00:27:51,760 --> 00:27:54,720
Speaker 1: then you can get up into this conduction band where

551
00:27:54,760 --> 00:27:57,200
Speaker 1: you can like float around between the atoms. So high

552
00:27:57,320 --> 00:28:01,640
Speaker 1: energy electrons can jump between them, but low energy electrons

553
00:28:01,640 --> 00:28:03,959
Speaker 1: are sort of stuck in their atom. So there's like

554
00:28:04,000 --> 00:28:06,080
Speaker 1: the cool kids that are running all over the neighborhood

555
00:28:06,400 --> 00:28:08,000
Speaker 1: and then the ones where their parents tell them they

556
00:28:08,000 --> 00:28:09,800
Speaker 1: have to stay home. They're all mixed together. Yeah, and

557
00:28:09,800 --> 00:28:12,439
Speaker 1: there's two different kinds and so based on how much

558
00:28:12,520 --> 00:28:14,080
Speaker 1: energy you have, and so that's what we call this

559
00:28:14,240 --> 00:28:17,240
Speaker 1: band gap. There's this energy gap. If you're above a

560
00:28:17,280 --> 00:28:20,280
Speaker 1: certain energy that you can move around and below that

561
00:28:20,320 --> 00:28:22,760
Speaker 1: you can't move around. And so that's what a semiconductor is.

562
00:28:22,760 --> 00:28:25,920
Speaker 1: And it's fascinating because it has this band gap. And

563
00:28:25,960 --> 00:28:27,800
Speaker 1: as you said, if you excite the electrons, you can

564
00:28:27,880 --> 00:28:30,720
Speaker 1: turn into a conductor. And but some of the electrons

565
00:28:30,880 --> 00:28:33,280
Speaker 1: they're low enough energy then they're an insulator. So you

566
00:28:33,320 --> 00:28:36,359
Speaker 1: get this sort of fine grain control about the electrical flow,

567
00:28:36,400 --> 00:28:38,640
Speaker 1: which is what makes it good for building circuits and

568
00:28:38,680 --> 00:28:40,520
Speaker 1: all sorts of stuff. But it's it's not a question

569
00:28:40,520 --> 00:28:43,200
Speaker 1: of the energy of the electrons, right, It's more of

570
00:28:43,200 --> 00:28:45,400
Speaker 1: a question of the kind of the energy of the

571
00:28:45,440 --> 00:28:48,640
Speaker 1: medium of the material. Yeah, the material determines sort of

572
00:28:48,640 --> 00:28:52,640
Speaker 1: this structure, right. Different kinds of semiconductors have different size

573
00:28:52,680 --> 00:28:54,880
Speaker 1: band gaps, but that band gap is the energy of

574
00:28:54,920 --> 00:28:57,560
Speaker 1: the electrons that we're talking about. And you can build

575
00:28:57,640 --> 00:29:00,400
Speaker 1: all sorts of different kinds of semiconductors. And you can

576
00:29:00,440 --> 00:29:04,080
Speaker 1: build semiconductors based on like what material you use, like

577
00:29:04,280 --> 00:29:06,840
Speaker 1: the gallium, is it, silicon, is it some combination of

578
00:29:06,920 --> 00:29:09,520
Speaker 1: these two. You can build semiconductors that have a bunch

579
00:29:09,560 --> 00:29:12,760
Speaker 1: of extra electrons in them, so that's called P type,

580
00:29:12,800 --> 00:29:15,880
Speaker 1: like there's a bunch of extra electrons floating around. Or

581
00:29:15,920 --> 00:29:18,320
Speaker 1: there's semiconductors that are called N types that have like

582
00:29:18,600 --> 00:29:23,480
Speaker 1: empty holes where electrons should go. Yeah, so they're both semiconductors,

583
00:29:23,520 --> 00:29:26,200
Speaker 1: and they're both about Usually mean add a silicon, right,

584
00:29:26,280 --> 00:29:29,120
Speaker 1: with some sort of metal kind of infused in it. Yeah,

585
00:29:29,120 --> 00:29:31,240
Speaker 1: And so you often start with silicon and then you

586
00:29:31,440 --> 00:29:34,080
Speaker 1: add little bits of other stuff to make different kinds

587
00:29:34,160 --> 00:29:37,240
Speaker 1: and a diode is just an N type semiconductor right

588
00:29:37,280 --> 00:29:40,000
Speaker 1: next to a P type semiconductor. And what this means

589
00:29:40,040 --> 00:29:42,440
Speaker 1: it's very simple. It just means the electricity can flow

590
00:29:42,480 --> 00:29:45,000
Speaker 1: in one direction, and that's what a diode does. So

591
00:29:45,080 --> 00:29:47,120
Speaker 1: the P type has a bunch of electrons and the

592
00:29:47,280 --> 00:29:49,440
Speaker 1: N type has a bunch of holes for those electrons

593
00:29:49,480 --> 00:29:52,800
Speaker 1: to fall into. So the P type one has electrons

594
00:29:52,840 --> 00:29:56,240
Speaker 1: floating above this band gap that can move around, etcetera, cetera.

595
00:29:56,720 --> 00:29:59,280
Speaker 1: When you put a current over, they just fall into

596
00:29:59,280 --> 00:30:03,760
Speaker 1: the holes, and electrons jumping from high energy states to

597
00:30:03,960 --> 00:30:07,080
Speaker 1: low energy states is how you emit energy. So when

598
00:30:07,080 --> 00:30:10,280
Speaker 1: they do that, they release photons. So a diode is

599
00:30:10,320 --> 00:30:13,000
Speaker 1: just P type and N type stuck together. And a

600
00:30:13,120 --> 00:30:16,120
Speaker 1: light emitting diode is one where when the electrons fall

601
00:30:16,200 --> 00:30:19,480
Speaker 1: in they emit visible light. And it has to be

602
00:30:19,520 --> 00:30:22,440
Speaker 1: a special kind of material or is it still just

603
00:30:22,520 --> 00:30:24,719
Speaker 1: silicon with some kind of metal in it. It has

604
00:30:24,720 --> 00:30:26,520
Speaker 1: to be a special kind of material to get the

605
00:30:26,600 --> 00:30:29,120
Speaker 1: right color light. And so that's really the key, that's

606
00:30:29,160 --> 00:30:31,680
Speaker 1: the core physics for why blue L E d s

607
00:30:31,880 --> 00:30:35,440
Speaker 1: were so fascinating. The first LEDs people invented, this gap

608
00:30:35,560 --> 00:30:37,600
Speaker 1: was kind of small sort of hard to make it work.

609
00:30:37,640 --> 00:30:40,040
Speaker 1: And so when they fell from P type to N type,

610
00:30:40,080 --> 00:30:42,560
Speaker 1: they didn't have that much energy and they emitted mostly

611
00:30:42,600 --> 00:30:46,000
Speaker 1: in the infrared. And that for example, the LED that's

612
00:30:46,000 --> 00:30:48,240
Speaker 1: in your remote control, the when that controls your TV,

613
00:30:48,680 --> 00:30:50,720
Speaker 1: you don't see light coming out of the top of

614
00:30:50,760 --> 00:30:53,160
Speaker 1: the remote control because it comes out in a wavelength

615
00:30:53,200 --> 00:30:55,840
Speaker 1: you can't see it comes out of infrared light to

616
00:30:55,960 --> 00:30:58,479
Speaker 1: talk to your TV. But there's an infrared LED at

617
00:30:58,480 --> 00:31:00,560
Speaker 1: the top of your remote control. And those are the

618
00:31:00,560 --> 00:31:02,760
Speaker 1: first ones that are invented. Is actually back in the

619
00:31:02,840 --> 00:31:06,479
Speaker 1: sixties that they first came out with infrared LEDs, and

620
00:31:06,520 --> 00:31:09,160
Speaker 1: then the challenge was coming up with different kinds of

621
00:31:09,200 --> 00:31:12,920
Speaker 1: material to negotiate this like P type N type difference.

622
00:31:13,160 --> 00:31:15,640
Speaker 1: So you've got a larger gap so you have more

623
00:31:15,880 --> 00:31:18,520
Speaker 1: energy when they fell, so you have more energy and

624
00:31:18,520 --> 00:31:21,800
Speaker 1: the photons so they could be visible light. Uh So

625
00:31:21,840 --> 00:31:23,880
Speaker 1: it's all about the difference between the P and the

626
00:31:23,960 --> 00:31:27,240
Speaker 1: N types of materials. Okay, So it sort of depends

627
00:31:27,280 --> 00:31:28,960
Speaker 1: more on the N type and the on the size

628
00:31:29,000 --> 00:31:30,600
Speaker 1: of the hole. Now the hole is just a hole

629
00:31:30,600 --> 00:31:33,400
Speaker 1: for an electron. It depends on the gap between the

630
00:31:33,400 --> 00:31:35,400
Speaker 1: P type and the ND type. So you're right, it

631
00:31:35,440 --> 00:31:38,120
Speaker 1: depends on the type of material and the size of

632
00:31:38,160 --> 00:31:39,880
Speaker 1: this gap. And you're putting this P type of this

633
00:31:40,000 --> 00:31:42,400
Speaker 1: N type next to each other, and it's basically how

634
00:31:42,400 --> 00:31:44,680
Speaker 1: far they fall, Like, are they just stepping down from

635
00:31:44,680 --> 00:31:46,240
Speaker 1: the curb and they go oop and they just give

636
00:31:46,280 --> 00:31:48,280
Speaker 1: off a little bit of light or they jumping down

637
00:31:48,360 --> 00:31:50,960
Speaker 1: Niagara falls and screaming all the way down and giving

638
00:31:51,000 --> 00:31:53,280
Speaker 1: off a lot of energy. Oh, I see the electrons

639
00:31:53,320 --> 00:31:57,000
Speaker 1: go from the P type to the N type. They jump, Yeah, yeah,

640
00:31:57,360 --> 00:31:59,240
Speaker 1: they jump where they fall, you know, depending on whether

641
00:31:59,240 --> 00:32:02,920
Speaker 1: you believe the electro is gonna make decisions. Man, they're

642
00:32:02,920 --> 00:32:06,160
Speaker 1: pushed or pull more they're more like pulled, right, Yeah,

643
00:32:06,200 --> 00:32:08,600
Speaker 1: they're more like pulled. And so basically an led is

644
00:32:08,640 --> 00:32:13,760
Speaker 1: a bunch of electrons screaming. So make time you look

645
00:32:13,760 --> 00:32:17,680
Speaker 1: at your phone. Your phone is screaming, screaming photons at

646
00:32:17,720 --> 00:32:20,080
Speaker 1: you every time. Yeah, it's not just your brain that's

647
00:32:20,120 --> 00:32:22,640
Speaker 1: screaming from your Twitter feed. And the thing that's amazing

648
00:32:22,640 --> 00:32:25,320
Speaker 1: about this is that it's solid state, right, Nothing is

649
00:32:25,440 --> 00:32:28,440
Speaker 1: moving here. You don't have gas that's bouncing around, you

650
00:32:28,440 --> 00:32:31,120
Speaker 1: don't have metal that's heating up and cooling down. It's

651
00:32:31,200 --> 00:32:33,640
Speaker 1: just fixed and it's just like electrical circuit, and that

652
00:32:33,680 --> 00:32:36,720
Speaker 1: makes it last for a very very long time. It

653
00:32:36,880 --> 00:32:40,440
Speaker 1: lasts for like a hundred thousand hours before it finally breaks.

654
00:32:40,480 --> 00:32:42,680
Speaker 1: It like trust can scream for as long as you need.

655
00:32:43,040 --> 00:32:47,280
Speaker 1: That's what you're saying. That's right. Unfortunately, the life span

656
00:32:47,320 --> 00:32:50,200
Speaker 1: of electron it's very very long. It's doomed to a

657
00:32:50,200 --> 00:32:52,360
Speaker 1: long life of falling down this gap. I guess my

658
00:32:52,440 --> 00:32:54,400
Speaker 1: question is what keeps the light going? Like, once it

659
00:32:54,440 --> 00:32:56,920
Speaker 1: falls into the hole, wouldn't it just stay in the hole? Yeah,

660
00:32:57,000 --> 00:32:58,920
Speaker 1: it does, wouldn't it fill up all the holes? Well,

661
00:32:59,120 --> 00:33:01,040
Speaker 1: you have a current it and so you're pulling these

662
00:33:01,040 --> 00:33:03,160
Speaker 1: electrons out of the end type. So the whole thing

663
00:33:03,240 --> 00:33:05,760
Speaker 1: is connected to a current. Imagine like a battery powering

664
00:33:05,800 --> 00:33:09,720
Speaker 1: the led. It's sending fresh electrons into the p type

665
00:33:09,720 --> 00:33:12,400
Speaker 1: and pulling the electrons out of the end type. So

666
00:33:12,440 --> 00:33:14,480
Speaker 1: the whole thing is a circuit. It is like a waterfall.

667
00:33:14,520 --> 00:33:17,520
Speaker 1: It's like a continual waterfall exactly. It's just like a waterfall.

668
00:33:17,520 --> 00:33:19,880
Speaker 1: You're pumping on one side and then they scream on

669
00:33:19,920 --> 00:33:21,880
Speaker 1: their way down. It's more like a roller coaster because

670
00:33:21,880 --> 00:33:26,760
Speaker 1: of the screaming Yeah, that's right, because then they come

671
00:33:26,800 --> 00:33:29,200
Speaker 1: back down and then the card gets pulled over and

672
00:33:29,240 --> 00:33:31,800
Speaker 1: then up the rap again and then down and then screen.

673
00:33:31,960 --> 00:33:34,480
Speaker 1: Let's not think of it as electron suffering, but electrons

674
00:33:34,560 --> 00:33:36,240
Speaker 1: is having a lot of fun, that's right. And you know,

675
00:33:36,280 --> 00:33:38,360
Speaker 1: you might wonder why do people go on roller coasters

676
00:33:38,400 --> 00:33:40,600
Speaker 1: because they scream the whole time? Well, I guess they

677
00:33:40,640 --> 00:33:43,040
Speaker 1: like to scream, and so we can imagine that also

678
00:33:43,080 --> 00:33:48,440
Speaker 1: electrons are enjoying this ride. There's thrill seekers and they

679
00:33:48,480 --> 00:33:50,440
Speaker 1: seem to be happy to do it because LEDs last

680
00:33:50,520 --> 00:33:53,480
Speaker 1: for a hundred thousand hours and it's very very efficient.

681
00:33:54,000 --> 00:33:56,680
Speaker 1: Most of the energy that you're sending into this circuit

682
00:33:56,720 --> 00:33:59,920
Speaker 1: actually goes into emitting light. It's like more than fee

683
00:34:00,280 --> 00:34:03,479
Speaker 1: percent of the energy. That's ten times, ten times more

684
00:34:03,520 --> 00:34:07,440
Speaker 1: efficient than incandescent bulb. Yeah, ten times more efficient. And

685
00:34:07,520 --> 00:34:10,879
Speaker 1: the challenge is in finding the right gaps you get

686
00:34:10,880 --> 00:34:13,280
Speaker 1: the right energy level, so you get the right colors.

687
00:34:13,640 --> 00:34:16,040
Speaker 1: And so the first thing was infra red, and then

688
00:34:16,160 --> 00:34:19,680
Speaker 1: you know, infra red is the lowest frequency, the longest wavelength,

689
00:34:19,760 --> 00:34:21,560
Speaker 1: and then they figured out ways to make them longer

690
00:34:21,600 --> 00:34:24,200
Speaker 1: so they were visible and then longer, so you've got red,

691
00:34:24,280 --> 00:34:29,680
Speaker 1: You've got green, and then the challenge was blue LEDs. Alright,

692
00:34:29,760 --> 00:34:33,840
Speaker 1: let's get into the amazing discovery that was discovering blue

693
00:34:33,960 --> 00:34:36,240
Speaker 1: LEDs and why I got the Nobel Prize. But first

694
00:34:36,320 --> 00:34:52,879
Speaker 1: let's take a quick break. All right, Daniel, somebody got

695
00:34:52,880 --> 00:34:56,520
Speaker 1: a Nobel Prize for discovering the blue led. So what's

696
00:34:56,520 --> 00:34:58,560
Speaker 1: so special about blue led? I like the way you

697
00:34:58,560 --> 00:35:00,919
Speaker 1: make it sound like they discovered a blue l D Like, well,

698
00:35:00,960 --> 00:35:02,840
Speaker 1: I was sweeping up my lab and I found this

699
00:35:02,880 --> 00:35:05,440
Speaker 1: thing on the ground. Oh my god, it's a blue LED. Right,

700
00:35:05,960 --> 00:35:08,359
Speaker 1: It's just what I was looking for, because that's how

701
00:35:08,360 --> 00:35:11,000
Speaker 1: we discover particles, right, you know, like, oh my gosh,

702
00:35:11,000 --> 00:35:12,960
Speaker 1: look I found a towel particle, and now I get

703
00:35:12,960 --> 00:35:16,040
Speaker 1: a Nobel Prize. I didn't like design it or engineer

704
00:35:16,160 --> 00:35:18,400
Speaker 1: it or an invented, right, it should be more like

705
00:35:18,400 --> 00:35:22,879
Speaker 1: it as somebody designed inventive. Yeah, somebody invented the blue led,

706
00:35:22,960 --> 00:35:25,320
Speaker 1: which is sort of awesome and impressive. So we couldn't

707
00:35:25,360 --> 00:35:27,160
Speaker 1: just take a white l ED and put a blue

708
00:35:27,239 --> 00:35:29,160
Speaker 1: filter on it. Well, that's the thing. You can't make

709
00:35:29,200 --> 00:35:32,319
Speaker 1: white l d s without blue. Right before we had

710
00:35:32,360 --> 00:35:34,200
Speaker 1: blue l e d s, we had green, and we

711
00:35:34,200 --> 00:35:36,560
Speaker 1: had read and so you couldn't make white l e

712
00:35:36,680 --> 00:35:38,880
Speaker 1: d s. That's why blue l d s are so

713
00:35:38,960 --> 00:35:42,600
Speaker 1: important because with blue you can make the combination you

714
00:35:42,640 --> 00:35:45,520
Speaker 1: need to make white. And nobody wants in their reading

715
00:35:45,600 --> 00:35:48,640
Speaker 1: light a green light or a red light. You want

716
00:35:48,640 --> 00:35:50,800
Speaker 1: a white l e ED And you couldn't make white

717
00:35:50,800 --> 00:35:53,600
Speaker 1: without blue. You need the blue. You need the blue

718
00:35:53,680 --> 00:35:55,239
Speaker 1: to make the need the blue to make the white.

719
00:35:55,800 --> 00:35:58,760
Speaker 1: And that's why l ds have exploded in applications everywhere

720
00:35:58,800 --> 00:36:01,680
Speaker 1: because now they can make essentially any color because we

721
00:36:01,760 --> 00:36:04,279
Speaker 1: have the missing blue cool. So tell me what was

722
00:36:04,360 --> 00:36:06,839
Speaker 1: so hard about it and what's the physics behind it? Yeah,

723
00:36:06,880 --> 00:36:08,600
Speaker 1: and so it's sort of an interesting question, like it

724
00:36:08,760 --> 00:36:11,400
Speaker 1: really was an engineering puzzle, Like you just needed to

725
00:36:11,400 --> 00:36:13,600
Speaker 1: get the right material. You needed to get the right

726
00:36:13,640 --> 00:36:16,560
Speaker 1: material with the right thickness and configure it all correctly

727
00:36:16,640 --> 00:36:19,200
Speaker 1: to get blue. And it was tricky to get this

728
00:36:19,360 --> 00:36:22,359
Speaker 1: gap to be extra extra large, large enough to make

729
00:36:22,440 --> 00:36:24,880
Speaker 1: so that when the electrons go down that roller coaster

730
00:36:24,920 --> 00:36:27,480
Speaker 1: they scream for long enough to give you a blue photon.

731
00:36:28,120 --> 00:36:29,840
Speaker 1: And you know, it turns out to be something of

732
00:36:29,880 --> 00:36:33,520
Speaker 1: a condensed matter and solid state engineering problem and a

733
00:36:33,520 --> 00:36:35,719
Speaker 1: couple of Japanese people figured it out. You need some

734
00:36:36,040 --> 00:36:40,000
Speaker 1: mixture of gallium nitride with other silicon substrates and then

735
00:36:40,040 --> 00:36:42,480
Speaker 1: you can get this blue led. But I guess why

736
00:36:42,560 --> 00:36:44,200
Speaker 1: was it so hard? Like when you try to make

737
00:36:44,200 --> 00:36:47,879
Speaker 1: electrons jump that much, it would burn out or they

738
00:36:47,880 --> 00:36:50,280
Speaker 1: just wouldn't do it, or you know, they wouldn't scream

739
00:36:50,280 --> 00:36:53,560
Speaker 1: as much as you wanted to. What was the difficulty

740
00:36:53,600 --> 00:36:56,080
Speaker 1: in getting this right? It's just in finding one that

741
00:36:56,080 --> 00:36:58,520
Speaker 1: would work. You know, most things just didn't have this

742
00:36:58,600 --> 00:37:00,520
Speaker 1: large enough gap, and so it's just a finding a

743
00:37:00,560 --> 00:37:03,359
Speaker 1: material that had this gap and that also worked. Yeah,

744
00:37:03,360 --> 00:37:05,200
Speaker 1: and that also works. I mean, you can make a gap,

745
00:37:05,200 --> 00:37:07,920
Speaker 1: but it may not necessarily work to get the electrons

746
00:37:07,960 --> 00:37:10,880
Speaker 1: to flow across it, And so we can't necessarily predict

747
00:37:10,880 --> 00:37:12,640
Speaker 1: in advance whether something is going to work. So they

748
00:37:12,640 --> 00:37:14,200
Speaker 1: sort of had just had to search through lots of

749
00:37:14,200 --> 00:37:16,400
Speaker 1: different kinds of materials and try this and try this,

750
00:37:16,480 --> 00:37:19,319
Speaker 1: and have inside and inspiration and also just some luck

751
00:37:19,440 --> 00:37:21,719
Speaker 1: into making it work. And so that's why I think

752
00:37:21,719 --> 00:37:25,320
Speaker 1: it's interesting, like does this deserve a Physics Nobel Prize?

753
00:37:25,320 --> 00:37:29,600
Speaker 1: Like there's no new principle discovered here, There's no fundamental

754
00:37:29,960 --> 00:37:33,160
Speaker 1: revelation of the nature of the universe or space, time

755
00:37:33,360 --> 00:37:36,560
Speaker 1: or history or whatever. It was an engineering step forward,

756
00:37:36,560 --> 00:37:39,759
Speaker 1: which a deep respect for the engineering step forward. But

757
00:37:39,840 --> 00:37:42,720
Speaker 1: I think the reason it got the Physics Nobel Prize

758
00:37:42,920 --> 00:37:46,759
Speaker 1: is because of the huge impact on society. Really, you

759
00:37:46,800 --> 00:37:52,120
Speaker 1: guys look down on things that are useful. You're like, well,

760
00:37:52,160 --> 00:37:54,560
Speaker 1: you know, I think the original Nobel Prize was supposed

761
00:37:54,560 --> 00:37:57,960
Speaker 1: to be about things that shape society, and so I

762
00:37:57,960 --> 00:38:01,279
Speaker 1: think Alfred Nobel would probably be it. He pleased. But

763
00:38:01,480 --> 00:38:04,320
Speaker 1: more recently a lot of these prizes have been awarded

764
00:38:04,360 --> 00:38:08,200
Speaker 1: for like deep but maybe impractical discoveries about the nature

765
00:38:08,200 --> 00:38:12,320
Speaker 1: of neutrinos or gravitational waves. I see, that's right. Nobel

766
00:38:12,480 --> 00:38:15,800
Speaker 1: was an inventor, right, He wasn't a physicist, he was

767
00:38:15,840 --> 00:38:19,160
Speaker 1: an engineering exactly. You guys have co opted our prize exactly.

768
00:38:19,160 --> 00:38:21,239
Speaker 1: So in some sense this is like a return to

769
00:38:21,320 --> 00:38:25,560
Speaker 1: Nobel's roots, right. It's recognizing something of great import to

770
00:38:25,719 --> 00:38:28,560
Speaker 1: society because it has had a huge impact. It was

771
00:38:28,600 --> 00:38:32,640
Speaker 1: like the missing piece. There's nothing weird physically about blue.

772
00:38:32,680 --> 00:38:34,840
Speaker 1: It's just sort of the highest frequency and therefore the

773
00:38:34,960 --> 00:38:37,400
Speaker 1: last for us to put together. I said, so do

774
00:38:37,400 --> 00:38:39,760
Speaker 1: you think somebody should have gotten a prize, a Nobel

775
00:38:39,800 --> 00:38:42,839
Speaker 1: prize for discovering the Higgs boson, because the people who

776
00:38:42,840 --> 00:38:45,480
Speaker 1: wanted wanted for coming up sort of with the Higgs boson,

777
00:38:45,560 --> 00:38:47,440
Speaker 1: but the people who discovered it, it was mostly just

778
00:38:47,480 --> 00:38:50,520
Speaker 1: sort of engineering. Right. You just described my whole field

779
00:38:50,520 --> 00:38:53,480
Speaker 1: as mostly sort of just engineering, which is so many

780
00:38:53,520 --> 00:38:55,320
Speaker 1: it fastening the angles because I think you meant that

781
00:38:55,360 --> 00:38:59,040
Speaker 1: as a disc but you described as engineering. So I

782
00:38:59,120 --> 00:39:02,480
Speaker 1: hold engineering that at the highest esteem. That was actually

783
00:39:02,520 --> 00:39:04,480
Speaker 1: trying to pay you a compliment. You were trying to

784
00:39:04,520 --> 00:39:07,600
Speaker 1: elevate our field by describing ange. I appreciate that it's

785
00:39:07,600 --> 00:39:10,440
Speaker 1: aspiring to be useful. Well, I'm not even sure how

786
00:39:10,560 --> 00:39:13,080
Speaker 1: useful it is to discover the Higgs boson. But I

787
00:39:13,120 --> 00:39:16,920
Speaker 1: think the great innovation there was definitely having the idea

788
00:39:17,520 --> 00:39:20,319
Speaker 1: and finding it. I don't know how many big steps forward,

789
00:39:20,320 --> 00:39:23,719
Speaker 1: and me it's a huge effort and technological achievement, But

790
00:39:23,920 --> 00:39:27,000
Speaker 1: I don't know that we necessarily created anything new. We

791
00:39:27,000 --> 00:39:30,680
Speaker 1: certainly didn't make anything as fascinating and impactful as the

792
00:39:30,719 --> 00:39:33,600
Speaker 1: Blue Led. We just sort of confirmed an idea that

793
00:39:33,680 --> 00:39:36,439
Speaker 1: it was in people's minds, so we revealed something about

794
00:39:36,440 --> 00:39:38,520
Speaker 1: the nature of the universe, but something that sort of

795
00:39:38,600 --> 00:39:42,319
Speaker 1: had been suspected to exist already. But okay, so back

796
00:39:42,360 --> 00:39:44,560
Speaker 1: to the blue l d. That's important because now you

797
00:39:44,600 --> 00:39:47,399
Speaker 1: have blue, and with red and green you can make

798
00:39:47,520 --> 00:39:49,319
Speaker 1: white lights. So you can make any kind of color

799
00:39:49,680 --> 00:39:52,480
Speaker 1: now that you have blue lads. Yes, exactly, And so

800
00:39:52,719 --> 00:39:54,920
Speaker 1: these guys invented it in the nineties and then they

801
00:39:54,920 --> 00:39:57,080
Speaker 1: won the No About Prize for it a few years later.

802
00:39:57,640 --> 00:39:59,960
Speaker 1: That's how ladies work, and that's why there's important. So

803
00:40:00,080 --> 00:40:02,080
Speaker 1: the people who discovered the red ladies and the green

804
00:40:02,200 --> 00:40:04,920
Speaker 1: ladies also get a price, or only the one who

805
00:40:04,920 --> 00:40:09,600
Speaker 1: waited till the end and procrastinated to discover the missing

806
00:40:09,600 --> 00:40:12,680
Speaker 1: color get the prize. I feel like you have another

807
00:40:12,719 --> 00:40:16,960
Speaker 1: horse in this race here, your pro procrastination. I built

808
00:40:16,960 --> 00:40:19,080
Speaker 1: a whole career on it. Any Yeah, the lesson here

809
00:40:19,239 --> 00:40:21,319
Speaker 1: is weight and just sort of put the period at

810
00:40:21,320 --> 00:40:23,200
Speaker 1: the end of the sentence and you'll get the prize

811
00:40:23,320 --> 00:40:26,440
Speaker 1: for everybody else's work. Yeah, there you go. But in

812
00:40:26,440 --> 00:40:28,760
Speaker 1: a way, it's true, right, like the person who discovered

813
00:40:28,760 --> 00:40:30,280
Speaker 1: the red and the green one didn't get a prize,

814
00:40:30,280 --> 00:40:33,080
Speaker 1: but somehow, like you know, completing the triangle to get

815
00:40:33,120 --> 00:40:35,879
Speaker 1: white light made a bigger splash. The person who puts

816
00:40:35,920 --> 00:40:38,480
Speaker 1: the capstone on the top of the pyramid, right, is

817
00:40:38,480 --> 00:40:40,600
Speaker 1: the one that claims the prize, right, the one who

818
00:40:40,640 --> 00:40:43,080
Speaker 1: discovers the mass particles the one who But yeah, so

819
00:40:43,160 --> 00:40:45,680
Speaker 1: now we can make white light with LEDs that is

820
00:40:45,719 --> 00:40:50,320
Speaker 1: super efficient and also small, really small. Like maybe before

821
00:40:50,360 --> 00:40:54,000
Speaker 1: you couldn't make incandescent bulbs small enough for you know,

822
00:40:54,040 --> 00:40:57,120
Speaker 1: written and display kinds of screens, but now you can't

823
00:40:57,160 --> 00:41:00,320
Speaker 1: because you can can really really small yeah, because we

824
00:41:00,360 --> 00:41:03,400
Speaker 1: can print stomic conductor is using these lithography techniques to

825
00:41:03,440 --> 00:41:06,480
Speaker 1: be really really super tiny. And you know, we invented

826
00:41:06,520 --> 00:41:09,920
Speaker 1: these techniques mostly so we can make transistors really really small,

827
00:41:10,200 --> 00:41:13,040
Speaker 1: so we can make computer chips packed with all sorts

828
00:41:13,080 --> 00:41:14,680
Speaker 1: of little circuits on them. But we can also use

829
00:41:14,680 --> 00:41:17,560
Speaker 1: the same technology to make l E d s and LEDs. Remember,

830
00:41:17,600 --> 00:41:20,920
Speaker 1: are not monochromatic. They're not like tiny little lasers. Right,

831
00:41:21,160 --> 00:41:25,000
Speaker 1: Lasers shoot exactly one frequency, are very very tight band

832
00:41:25,040 --> 00:41:28,800
Speaker 1: and frequency because the photons come from one atomic step.

833
00:41:29,200 --> 00:41:31,640
Speaker 1: Ellis are not quite like that. The light they admit

834
00:41:31,719 --> 00:41:34,920
Speaker 1: is narrowly focused, doesn't have just a single wave length

835
00:41:35,080 --> 00:41:37,400
Speaker 1: or frequency. It's like it is a little bit like

836
00:41:37,440 --> 00:41:40,359
Speaker 1: in Contestant, and that it's kind of broad. Yeah. Yeah,

837
00:41:40,400 --> 00:41:43,040
Speaker 1: they're broader than lasers, but not as broad as in Contestant.

838
00:41:43,120 --> 00:41:45,400
Speaker 1: So that's why there are specific color, but they're not

839
00:41:45,480 --> 00:41:48,600
Speaker 1: like a really tight band like lasers. So then when

840
00:41:48,600 --> 00:41:50,960
Speaker 1: I turn on the flashlight on my phone and I

841
00:41:51,000 --> 00:41:53,680
Speaker 1: see this wide light come off, and that helps me

842
00:41:53,719 --> 00:41:56,400
Speaker 1: at night and get around at night, I'm actually seeing

843
00:41:56,920 --> 00:41:59,439
Speaker 1: not a white led, but like a whole bunch of red,

844
00:41:59,560 --> 00:42:01,920
Speaker 1: blue and green lads mixed together. That's right. And when

845
00:42:01,960 --> 00:42:04,799
Speaker 1: you look on your screen and you see white for

846
00:42:04,840 --> 00:42:06,879
Speaker 1: the blank page and the word document of the novel

847
00:42:06,920 --> 00:42:09,160
Speaker 1: you've been writing for ten years, than what you're really

848
00:42:09,239 --> 00:42:13,640
Speaker 1: seeing our red, green and blue blinking, your failure action blinking.

849
00:42:14,000 --> 00:42:15,839
Speaker 1: But you know, that's what Newton discovered is that white

850
00:42:15,920 --> 00:42:18,680
Speaker 1: light is actually just a mixture of colored lights. There's

851
00:42:18,680 --> 00:42:21,920
Speaker 1: no difference, There is no white photon, there's no color

852
00:42:21,960 --> 00:42:24,440
Speaker 1: in the spectrum that is white. White light is just

853
00:42:24,520 --> 00:42:27,719
Speaker 1: a mixture of red, green, and blue. And so basically

854
00:42:27,760 --> 00:42:33,200
Speaker 1: that increased our human level global efficiency for light by

855
00:42:33,440 --> 00:42:36,040
Speaker 1: ten times. So now we can be a whole lot

856
00:42:36,080 --> 00:42:38,759
Speaker 1: more eco friendly. Yeah, except probably just means we made

857
00:42:38,800 --> 00:42:40,959
Speaker 1: a lot more bulbs, so probably using the same amount

858
00:42:40,960 --> 00:42:44,520
Speaker 1: of electricity, and now we're just lighting everything up. You know,

859
00:42:44,640 --> 00:42:46,680
Speaker 1: I changed all the light bulbs in my house for

860
00:42:46,800 --> 00:42:50,279
Speaker 1: l d s and boy, your power bill drops like crazy. Yeah. Well,

861
00:42:50,280 --> 00:42:52,520
Speaker 1: do you appreciate it though? For working? Like when you're

862
00:42:52,600 --> 00:42:56,400
Speaker 1: drawing something, do you like using natural light or incandescent

863
00:42:56,480 --> 00:42:58,480
Speaker 1: light or LED light or does it not make any

864
00:42:58,480 --> 00:43:02,040
Speaker 1: difference because you do everything at well, I drive everything

865
00:43:02,080 --> 00:43:07,560
Speaker 1: on the computer, so it's all LED power, baby, you know, yeah,

866
00:43:07,560 --> 00:43:10,680
Speaker 1: I guess so. All right, Well that's pretty cool. I

867
00:43:10,719 --> 00:43:13,600
Speaker 1: have a new respect for blue lads now, and also

868
00:43:13,680 --> 00:43:15,640
Speaker 1: liver respy for red and green lads. You know, I

869
00:43:15,640 --> 00:43:18,280
Speaker 1: feel like they got the short end of the colored triangle.

870
00:43:18,320 --> 00:43:20,680
Speaker 1: They are singing the Nobel Blues, all right, but I think,

871
00:43:20,880 --> 00:43:23,479
Speaker 1: you know, it points us to how even a small

872
00:43:23,480 --> 00:43:27,240
Speaker 1: discovery in physics or experimental physics can lead to basically

873
00:43:27,360 --> 00:43:30,640
Speaker 1: revolution and how we lead our lives and what kinds

874
00:43:30,680 --> 00:43:33,600
Speaker 1: of devices we use every day. That's right. Engineering can

875
00:43:33,680 --> 00:43:37,719
Speaker 1: change to the world. What can you guys replay that?

876
00:43:37,800 --> 00:43:39,080
Speaker 1: Which is one more time? I just want to make

877
00:43:39,120 --> 00:43:41,160
Speaker 1: sure that we heard it right. Can you replay it?

878
00:43:41,360 --> 00:43:46,359
Speaker 1: Engineering can change to the world. You know, I'm gonna

879
00:43:46,400 --> 00:43:49,640
Speaker 1: download it, frame it, frame it on an led frame.

880
00:43:49,840 --> 00:43:51,279
Speaker 1: I should send you a little button. You can just

881
00:43:51,280 --> 00:43:54,600
Speaker 1: press that and hear me say that. Hag into your

882
00:43:54,600 --> 00:43:59,080
Speaker 1: phone and make it your ring tone. All right. Well,

883
00:43:59,480 --> 00:44:01,560
Speaker 1: we hope you joined that, and we hope you look

884
00:44:01,600 --> 00:44:04,279
Speaker 1: at light in a whole different light. Thanks for tuning in,

885
00:44:04,320 --> 00:44:14,680
Speaker 1: See you next time. Thanks for listening, and remember that.

886
00:44:14,800 --> 00:44:17,520
Speaker 1: Daniel and Jorge Explain the Universe is a production of

887
00:44:17,640 --> 00:44:21,000
Speaker 1: I heart Radio. For more podcast from my heart Radio,

888
00:44:21,160 --> 00:44:24,720
Speaker 1: visit the i heart Radio app, Apple Podcasts, or wherever

889
00:44:24,840 --> 00:44:32,160
Speaker 1: you listen to your favorite shows. Yeah,