Daniel and Jorge Explain the UniverseDaniel and Jorge talk about how our understanding of physics is central to making the internet work.
See omnystudio.com/listener for privacy information.
If you love iPhone, you'll love Apple Card. It's the credit card designed for iPhone. It gives you unlimited daily cash back that can earn four point four zero percent annual percentage yield. When you open a high Yield Savings account through Apple Card, apply for Applecard in the wallet app subject to credit approval. Savings is available to Apple Card owners subject to eligibility. Apple Card and Savings by Goldman Sachs Bank USA, Salt Lake City Branch Member FDIC terms and more at applecard dot com. When you pop a piece of cheese into your mouth, you're probably not thinking about the environmental impact. But the people in the dairy industry are. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. How is US Dairy tackling greenhouse gases? Many farms use anaerobic digesters to turn the methane from manure into renewable energy that can power farms, towns, and electric cars. Visit us dairy dot COM's Last Sustainability to learn more.
And friends and families walking riding on passing the roads every day. Remember they're real people with loved ones who need them to.
Get home safely.
Protect our cyclists and pedestrians because they're people too, Go safely, California. From the California Office of Traffic Safety and Caltrans.
We're just days away from our twenty twenty four iHeartRadio Music Festival, presented by Capital On. The biggest headliners in live music will be taking over to Mobile Arena, Las Vegas.
Loss some special surprises at moments you are not going to want to miss.
Stream only on Hulu iHeartRadio Music Festival and listen on iHeartRadio the most anticipated live music events of the.
Year this Friday and Saturday, starting at ten thirty pm Eastern, seven thirty Pacific.
Hey Daniel, do you think we could do physics without the Internet?
Well, I mean there was a lot of physics done before the Internet, So yeah, do.
You think the Internet distracts you or helps you?
I'm sure it distracts me, but also lets me look stuff up.
When you can do physics by just looking stuff up.
Sometimes you got to know the mass of the electron and who remembers that stuff anyway.
Don't you think maybe like Newton would have done a better job if he had the Internet? Available at the time, or would have been just stug watching cat videos.
I think watching cats fall out of trees might have inspired his ideas in gravity even earlier.
Oh boy, like he had the original cat video. But I wonder if he would be more popular if we had more cat episodes.
I'll drop one cat per episode.
I promise, yes, we need new categories.
Hi.
I'm morhem and cartoonist and the author of Oliver's Great Big Universe.
Hi. I'm Daniel. I'm a particle physicist, professor at UC Irvine, and I really wish I had cats.
You wish you had cats?
I do.
Why did you just get some cats?
I have kids and they are allergic to cats. Unfortunately, I used to have cats before I had kids. That's easily remedied, Daniel, I'm terrified. Just depends how much you want the cats. You know, Well, the kids also want cats, so they're actually taking algae shots in hopes that we can one day have a cat.
Uh.
Like those treatments where you get exposed a little bit at a time, m M. Exactly like one cat air at a time, m hm.
Just like this podcast is exposing everybody to physics a little bit at a time inoculating them against the disease.
So if you go too strong on this podcast, people will get the hives.
You could get a reaction, but choke, I've seen that reaction. Not pretty.
No, yeah, it just makes you sleepy.
I guess their mental immune system rises up in defense.
It just makes people pass out. If we go too deep into particle physics, it acts like Benadrul and just knocks people out. But anyways, welcome to our podcast, Daniel and Jorge Explain the Universe, a production of iHeartRadio.
In which we go as deep as we can into particle physics and cosmology and astrophysics and astronomy and all the different kinds of physics that help explain this amazing, beautiful, bonkers universe that we live in. We think it all makes sense, and we want it all to make sense to you.
That's why we try to be the Hives of curiosity and try to inoculate you against the mysteries of the universe by talking about all of the things that we know and maybe don't know about.
The Cosmos and physics has always relied on conversation, people talking about how things work, people brainstorming together, people writing elaborate letters to each other about what orbits what in the solar system. Communication has always been an inherent part of physics, and physics has always enabled communication.
I guess all signs, not just physics. It's kind of this mix of individual thought and pondering, but also this mix of talking to your peers and sharing your ideas and where you're at.
Right, Yeah, exactly. Brainstorming is such an essential part of it. I can't count the number of times I've had a bad idea, suggested it to somebody and it's inspired a better idea in them. Yeah.
I guess we all need that person to like check our ideas, right.
Yeah, we all need that person have a good idea in response to our dumb idea. That's why I.
See, and then becomes your idea.
Then becomes our idea.
Did you just reveal your whole plot here for how to exploit graduate students and steal the ideas.
Collaborating with graduate students is not a well kept secret.
I see you call it collaborating. Got its collaborative, that's a safe word. They get to be first author, that's true. But yeah, as you said, it's all about communication, and it seems like communication just for the entire human race has sort of accelerated at lightning speed with the advent of the Internet.
Exactly because communication facilitates physics, but also discoveries help us find new ways to communicate even faster, more cat videos all day long.
I guess even in the old days, like if you sent a letter across the Atlantic, you relied on physics to you know, keep the wagon rolling down to the coast, and then you need physics to keep the boats afloat right as it crosses and takes your letter across it the Atlantic. Couldn't you just say everything is physics, like my cereal is physics. It's also chemistry, maybe math.
That's right, But physics is also the reason why we're not using wagons in boats anymore. You know. Development of electronics meant we could send telegraphs to each other, Cathode raid tubes meant we can invent screens to look at stuff. Radio waves allowed for wireless communication around the planet. Physics has helped change how we communicate.
Or I think you just said it.
Electronics help change everything, and for that we are thankful to electronic engineers.
As perhaps absolutely the Internet relies on engineers, but the principles are physics are what created these new opportunities.
Well, I guess I wonder if that's debatable, or maybe it depends on a case by case basis. Like sometimes we, like engineers or anyone, discovers an effect and they figure ou how to use it, and then they discover what's going on behind it.
Right, you need to give an example.
No, I can't give you an example.
Very persuasive.
Yeah, if I ask you for an example, yeah, sure.
Well you know, cathode raise, we're definitely discovered not by physicists, but then understood by physicists, and then the application of them to developing screens relied on that physics understanding. So cathoid ratubes, for example, were in sideshows and demonstrations and even like circuses well before JJ Thompson understood that they were electrons.
Mmm. So it sort of starts with non physicists, then physicists jump in, we understand it a little bit better, and then we understand it a little bit better enough to use it for things.
Yeah, exactly. Or you know the foundation of modern computing, our transistors, and without quantum mechanics, we definitely wouldn't understand all the energy levels and the electron flows and be able to build such miniaturize little switches that definitely run the Internet. So physics is essential there as well.
Yeah, so it seems like there's physics in our everyday lives and in our everyday surfing of the web as well. So to you on the progium will be taging the question what physics is behind the Internet? Wait, there's something behind the Internet. There's a secret cabal, there's death through the Internet.
You can only see the surface layer, but us physicists have access to the next dimension of the Internet.
WHOA You make it sound like it's the matrix in your neo. Is that what it is all about?
Yes, this is secret council of physicists that run the Internet and decide what you see every day.
Totally all right, So it seems like that we're going to be talking about some of the physics the facts or principles then power the Internet or that make the Internet possible.
Yeah, exactly what physics do you have to know if your civilization and you want to build an Internet.
Well, as usually, we were wondering how many people out there had thought about this question.
Thanks everybody who volunteers, and if you would like to join this group, please don't be shy wright to me two questions at Daniel and Jorge dot com. We really do want to hear your voice.
So think about it for a second. How many physics principles can you name in the use of the Internet. Here's what people have to say.
Particle or nuclear physics as World Wide Web was designed for and within CERN at the time. Other than that, well for the all radio communications to satellze through Wi Fi, all electromagnetism and forty five cables, all the photone and the crystal stuff, and then the routers and everything. Just all electromagnetism, but there are a lot of solid state physics too with the storage running the Internet and so on and so on.
So I think this is all about electrons moving around back and forth to communicate and create ones and zero so that we can transmit information.
When I think about the physics behind the Internet, I think of, first off, the power requirements to run all of the data centers and servers and our computers and our desks, and then you think about the infrastructure that supports it, from undersea cables to data cables and fiber optic lines and all of the infrastructure built just to transmit information. Is that physics, Well, physics went into building or designing it. But that's the first thing I think of.
There's got to be a whole lot because there's so many elements of the Internet from the actual signals that we passed, whether that'd be electrico or optico or radio or microwave, gectual devices that process backets have micro controllers and storage devices, and I think they need to worry about quantum effects and dot scale. And then we have satellite orbit that probably needs to do corrections for general relativity. So a whole lot of physics.
All right, A lot of interesting answers here. I feel like, at some point, though, isn't physics behind everything? And isn't mad behind all the physics, etcetera, etcetera. Like you could say, what are the physics behind cereals or herbology?
In principle, you might be able to tear the universe apart down to its tiniest little bits, understand those rules, and put it back together to make sense of everything. But in practice that's not the way we do science. To do science at various different layers where things emerge and we discover the rules that guide them. So you know, we have like fluid mechanics, and we have chemistry, and we have economics, and we could in principle say why people buy sneakers is physics, but really it's a different kind of science governed by different kinds of rules. So I don't think it's fair to say everything is physics.
Well, these days it seems like the Internet is everything. And say, we're going to be talking about some of the technologies behind the Internet and what physics there is behind those technologies, m.
Exactly, And there are lots of bits of the Internet that really do rely on physics, where understanding of how things work at the smallest scale, or revolutions in that understanding have allowed us to do all the great awesome stuff we do online.
All right, well, let's start maybe at the beginning of the internet. The Internet you need computers for that.
Yeah, that's right. The Internet is a big connected set of computers. And you're absolutely right. Unique computers in order to have an Internet, and computers actually come out of mechanical engineering, you know, like Ada Loveless and Charles Babbage. Back before we had electronics. All modern computers, of course, are digital and electrical, and so you have to understand something about electricity in order to build a modern computer.
Well, this kind of raises an interesting question, like what exactly do you call the Internet? Like we all use the word, we all use the internet, but like if you had to define what the Internet is, what would you say it is?
I would say the Internet is a bunch of computers all connected on a network with a very specific protocol. The way we send messages back and forth is a very specific algorithm for how to get information from one side of the world to another. So that's what I would call the Internet. You can have other kinds of networks, but this is one specific way to connect everything.
It's like the infrastructure that enables you to just plug your computer into the wall so they can talk to other computers. But it's also sort of like the Like you said, the protocol is the software and the standards that everyone agrees to. Like if I want to send a message to someone in Russia, you have to go use certain protocols about how do you call that address? In what format you send stuff?
Right?
How those computers shake hands and communicate with each other exactly.
You basically have to agree to participate in this huge thing called the Internet. And when you plug into the Internet, it's not like mail. It's not like you only get stuff that was sent for you. You get a bunch of stuff send for other people and you agree to pass it along towards them. The Internet has this really complex packet switching model for getting data from one side of the world to the other, and everybody that connects to it participates in it. So that's what the Internet is. A bunch of computers connected, of course, but then also the way that everybody agrees to participate.
There could be multiple internets for example, right, just like for example there is the US Postal Service, and there's also UPS, there's also FedEx. There are like different networks of things that let you move things around that. The Internet is one of those things.
Yeah, the Internet is one of those things. And back in the day, there used to be multiple different networks, you know, there were these building board services, there were other little local networks. The Internet is really the growth of the global network that ties them all together into one meta network.
Well, like you said, it requires computers and wires, and some of that requires physics to understand what's going on and also just to kind of squeeze as much data out of these wires and connections as much as possible.
Yeah, and at their heart, computers these days are built out of electrical wires and switches. So you have electrical currents are sending information down the wires, and then you have things like transistors that are flipping bits, turning things on and off, making decisions, changing that dynamically, so you don't just have like a fixed circuit that does the same thing every time. You have a programmable circuit. They can also adjust itself and change its own behavior. That's what makes a computer so powerful is that it can do any kind of calculation, not just one fixed kind of calculation. It's like the difference between a piano and a CD of somebody playing a one song on the piano. Piano lets you play anything, the recording only plays the one song.
So where would you say, is a physics in those wires or like, how has physics helped does transmit information faster?
Yeah, so understanding electricity has helped us transmit information at the speed of light all the way back to the telegraph, which is definitely not part of the modern Internet, but it's sort of part of the origins of it. That was really a revolution understanding how you could send electrical pulses down wires to wiggle something at the other end using electromagnetism where you're turning magnets on and off to shape this telegraph receiver. This allows us to transmit information at what was effectively instantaneous speeds compared to you know, letters and ponies and carrier pigeons and whatever else they had just before the telegraph. So that really shrunk the whole world. And it's the same principle that operates inside your computer right now, to transmit information around the computer and then along the network, and then along the cables between the computers. So that understanding of electricity really changed how rapidly we could communicate over long distances.
And I think these days it gets even more physics ly, like basically, the wires between here and Europe, they're not electrical at this age, right, I think it's either optical fibers or through satellites, right.
Yeah, absolutely, Optical fibers are a great way to send information, and for that you don't need to understand electricity, but you do have to understand light is of course related to electricity, and you have to understand optics and how to make long tubes of glass and all sorts of stuff. The crucial physics concept of fiber optics is called total internal reflection. But it's not that hard to understand. When light hits a surface like air to glass or air to water or whatever, the way it wiggles on the two substances on either side of that surface is different because they're different substances. But at the surface in between them, the interface, the electromagnetic field has to line up and make both sides happy. That's why, for example, light bends at an interface. It's the only way to get both sides of the field on both sides of the surface where the wavelengths are different. To line up nicely. The light has to have a different angle on one side of the surface than the other. But if the angle on one side is just right and you pick the materials carefully, then there's actually no way to get the light waves to line up on both sides. The wavelength and the coding on a fire fiber optic cable is too long to get any matches at that boundary, and so because there's no way to have light in the coding, you get total internal reflection because the light goes down the fiber and none of it escapes. So that's some crucial bit of physics for making fiber optics work, which is an essential part of the Internet. And then satellite networks of course rely on wireless technology, so there's physics all over those networks.
Yeah, and how you transmit information. But also there's physics in how you actually make computations, right, And like computers are based on transistors and transistors they have their origin in mechanical thinking and logical machines, but nowadays it's all like semiconductors, right, and super super tiny almost quantum size devices.
Yeah, the origin of them are pretty simple. They're just like a mechanical switch. You want to turn something on, you want to turn something off, you want to set a value in the computer memory where you want to change how two things are connected to add numbers or subtract numbers. And back in the day you could build these things using mechanical relays or other sorts of devices. But these days, in order to have very fast computers, computers so they can do a lot of calculations so they can render that cat falling off the tree, or they can support your latest video game or whatever. Then you got to miniaturize all those relays. It's a big mechanical relay. It takes time to switch because it's so big. You know, you send the signal to complete the current and the thing like slides over. You know, it takes milliseconds, and that limits how fast you can do calculations. If you need lots of those switches to flip. What you want are small fast switches because the faster they switch, the faster your computer is. And that's why you want to shrink them down because then everything goes faster.
And sometimes I think the technology behind these computers of suddenly changes, Like we went from vacuum tubes, which totally different than how they work now, which is silicon wafers.
Exactly because we have new ideas for how to support it. In the end, it's sort of philosophical, like it's just representing information and how that information adjusts itself. In principle, you could do that and lots of different media, lots of different substrates could support computation. And we haven't even gotten into you know, quantum computers, so they're not really even part of the Internet yet. But silicon is a really nice way to do it, but it requires a bunch of techniques all coming together. One is like how to actually build those transistors, And those transistors are built on the principle of semiconductors, like understanding how electrons flow through some materials and don't flow through other materials, and how you can change that by applying voltages on them.
Back in the day, they had mechanical computers, right, like you can use machines like levers, mechanical machines to do these computations.
Yeah, and principle, you could build a computer out of anything, you know, tubes of plasma in the sun or whatever. As long as you can control it, you can develop logic based on it. The semiconductors are a really nice way to do it because we can miniaturize them because we have the technology from making these very thin wafers of silicon for printing the circuits onto them, and so it's been decades we've been making these things smaller and smaller and smaller. And the way that the transistors actually work relies on a really subtle bit of physics, which in the end is quantum mechanical. Like if we hadn't discovered quantum mechanics, we would not be able to build transistors out of semiconductors.
All right, let's get into how quantum physics is maybe changing computers and competitions, and then let's talk about some of the other ways that physics figures into the Internet.
But first let's take out quick great.
With big wireless providers, what you see is never what you get. Somewhere between the store and your first month's bill, the price you thought you were paying magically skyrockets. With mint Mobile, you'll never have to worry about gotcha's ever again. When Mint Mobile says fifteen dollars a month for a three month plan, they really mean it. I've used mint Mobile and the call quality is always so crisp and so clear. I can recommend it to you, so say, but by to your overpriced wireless plans, jaw dropping monthly bills and unexpected overages. You can use your own phone with any mint Mobile plan and bring your phone number along with your existing contacts. So dit your overpriced wireless with mint Mobiles deal and get three months a premium wireless service for fifteen bucks a month. To get this new customer offer and your new three month premium wireless plan for just fifteen bucks a month, go to mintmobile dot com slash universe. That's mintmobile dot com slash universe. Cut your wireless bill to fifteen bucks a month. At mintmobile dot com slash Universe. Forty five dollars upfront payment required equivalent to fifteen dollars per month New customers on first three month plan only speeds slower about forty gigabytes on unlimited plan. Additional taxi speeds and restrictions apply. See mint mobile for details.
AI might be the most important new computer technology ever. It's storming every industry and literally billions of dollars are being invested, so buckle up. The problem is that AI needs a lot of speed and processing power. So how do you compete without cost spiraling out of control. It's time to upgrade to the next generation of the cloud. Cloud Infrastructure or OCI. OCI is a single platform for your infrastructure, database, application development, and AI needs. OCI has four to eight times the bandwidth of other clouds, offers one consistent price instead of variable regional pricing, and of course nobody does data better than Oracle. So now you can train your AI models at twice the speed and less than half the cost of other clouds. If you want to do more and spend less, like Uber eight by eight and Data Bricks Mosaic, take a free test drive of OCI at Oracle dot com slash strategic. That's Oracle dot com slash Strategic Oracle dot com slash strategic.
If you love iPhone, you'll love Apple Card. It's the credit card designed for iPhone. It gives you unlimited daily cash back that can earn four point four zero percent annual percentage yield. When you open a high Yield savings account through Applecard, apply for Applecard in the wallet app, subject to credit approval. Savings is available to Applecard owners subject to eligibil Apple Card and Savings by Goldman Sachs Bank USA Salt Lake City Branch Member FDIC terms and more at applecar dot com. When you pop a piece of cheese into your mouth, or enjoy a rich spoonful of Greek yogurt, you're probably not thinking about the environmental impact of each and every bite, But the people in the dairy industry are US. Dairy has set themselves some ambitious sustainability goals, including being greenhouse gas neutral by twenty to fifty. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. Take water, for example, most dairy farms reuse water up to four times the same water cools the milk, cleans equipment, washes the barn, and irrigates the crops. How is US dairy tackling greenhouse gases? Many farms use anaerobic digestors that turn the methane from maneure into renewable energy that can power farms, towns, and electric cars. So the next time you grab a slice of pizza or lick an ice cream cone, know that dairy farmers and processors around the country are using the latest practices and innovations to provide the new two intense dairy products we love with less of an impact. Visit usdairy dot com slash sustainability to learn more.
All right, we're talking about the physics of cat videos now, Daniel, is there a physical way to quantify the cuteness of a kitten?
See, that's not physics at all, that's sociology. Or psychology. There are sciences, you know.
I feel like you're cherry picking. Like, if you want to take credit for it, you call it physics. If you don't want to take credit for it, you call it something else. There is this very suspicious strategy you got here.
No. No, I would love to take credit for why cats are cute. I would love to be able to explain to you because the weak force works in this way. Therefore your brain thinks cats are cute. But I can't do that. There's no way I can connect particle physics to cats are cute.
Brain chemistry. There, I see, I see.
What can you connect particle physics to IP addresses?
No, but I can connect partic physics to the World Wide Web. We'll get there eventually.
Hmmm, all right, we'll get to that in a minute.
But we were talking about quantum mechanics and how they figure into the sort of super tiny transistors that are made out of silicon. But looking a little bit into the future, they might also just totally revolutionize computers with the advent of quantum computers as well. Right in those cases, you're not using silicon transistors, are you.
Yeah, Quantum computers can be based on lots of different technologies. They're not fundamentally based on bits the way we think about them. For normal computers, which are these little transistors that can be in the state of zero or one, but they're based on cube bits and a cubit is kind of like a generalization of a classical bit, but it's not necessarily in a state of zero or one. It has probabilities to be in various states. So it's a different kind of computation, like the way that we think about logic and manipulating information. That's one kind of computation, but there are other kinds of computation take advantage of what the physical world is doing to extract an answer to your.
Question, But do you think all computers will eventually be quantum computers or do you think quantum computers will only be useful in certain applications.
There's nothing a quantum computer can do that a classical computer cannot do. It's just a question of can they do it more efficiently, And there are a few examples where people think if you build a large error correct and quantum computer, you can do those calculations faster on quantum computers than normal computers. But they're really very narrow and limited. So even though there's a huge amount of hype about quantum computers, I haven't seen a whole lot of persuasive arguments that quantum computers are anywhere in the near future going to revolutionize like what we call computing and the kind of problems we can solve. But of course it's naive to say we know everything quantum computers could ever do. It's always exciting to have a new kind of thing, a new kind of computer, and the kinds of things people will do with them aren't things we can imagine right now, so it's definitely valuable research. I just think it's actually more exciting to not know what they're going to be useful for. But right now people feel the need to sell them with a specific killer app, which I think is sometimes a bit overdone.
But in terms of making computers smaller and smaller, we are sort of starting to get into the quantum realm, right Like some of these transistors now that you can fit like billions bazillions of transistors into a tiny market chip, Like, the size of these transistors are now getting to the point where you do kind of have to start thinking about the quantum mechanics of it, right.
You have to think about the qutum mechanics of it, no matter the size of your transistor. Like there's quantum mechanics and the basic principles of a transistor, and it all comes from the quantum mechanical understanding of how an atom works. In an individual atom, we know electrons have energy levels. Like the classical picture is you have a proton the nucleus of a hydrogen atom, for example, and electrons exist in various states around it. But the electron has to be in one of these states. It's like specific energy levels that solve all the equations of quantum mechanics. The electron can't just have an arbitrar energy. It's like a ladder there. So that's a single atom. It's sort of a simple picture. As you bring a bunch of atoms together to make like a blob of stuff, you know, like silicon or geranium or something else, then the energy levels get a little fuzzier because now your electrons are interacting with more than one nucleus. So instead of having the same crisp energy levels from a single atom, now you have these like bands of energy levels. The electrons can live in like more energy levels with finer steps between them, but then also groups of them like lower energy levels, and then a band of higher energy levels. Those bands of energy levels, rather than just some simple tomic spacing, is the physics behind why some materials are conductors and some are insulators. The lower bands are usually full, so electrons can't move, like if you're packed into a totally full elevator. To move is an electron, you have to jump into an empty upper band, So insulators tend to have a big gap between the bands, so electrons are mostly stuck in the lower bands and can't move around in the empty bands above. Conduct have a small gap, so it's easy for the electrons to jump up and move freely. Semiconductors have an intermediate gap that can be tweaked and tuned by adding various materials to the silicon, so that lets you do clever material engineering to make things like one way path for electrons from one sized gap to another. That's what a diode is. You can put the diodes together and the materials together in more complex ways and you get like a transistor, which is basically a quantum mechanical switch, and that's the basis of all modern computing, right right.
But I wonder if that's more in a classical physics side. I mean, I know you need quantum mechanics to understand in that, but like you don't need to know the Heisenberg uncertainty principle to make a vacuum tube work.
For example, you don't need to know the Heismberg and certain principle to make a vacuum tube work. That's true, you can build switches without quantum mechanics, but if you want to build amount of transistors, which is crucial for making them really really small, then you got to know the quantum mechanics. You've got to understand how to make a conductor or an insulat or a semiconductor, all these kind of things. These are the foundation of modern transit.
Right right.
But like to make one work, like the early transistors, you didn't really need to be thinking about wave functions or probabilities to make them work and use them.
The first solid state transistors, which are built out of semic conductors, you absolutely did. The previous ones are not solid state, they are like mechanical. Those you don't need to understand quantum mechanics.
Yeah, you need physics to understand everything, Daniel.
Like to use them like it might be first computers or even like the my phone today doesn't really take into account things like the wave functions of the atoms and the transistors.
Do they Your phone has transistors which are based on semic conductors, and understanding the energy level of semic conductors requires quant mechanics. Absolutely, you can't do that with classical physics.
Understanding them, yes, but to make them work. And what I'm saying is we haven't needed to really dig into the quantum mechanics. But as these transitionors get even smaller, they are going to be even more important to know that the quantum mechanics that are happening.
Yeah, I think quantum mechanics is going to continue to be vital. I think the issue for getting them even smaller is the technology of just making them smaller. Can you physically build these things, like actually assemble this device that has like a single row of atoms here in a single row of atoms there. I think the quantum mechanics actually becomes a little simpler as they get smaller, because you have fewer atoms to deal with.
All right, Well, so then that's the physical substrate on which the Internet is based on. I think you're also trying to make the argument that the communication part of it also depends on physics.
Yeah, once you have these computers and they're cranking along and they're doing their calculations on their silicon chips, then you want to stick them together. Right, it's not on the Internet if they're not stuck together. And the way you connect them is with these wires or the fiber optics or the satellites, and that's sending information. And all of those technologies, even just electrical pulses, fiber optics, sound light technology, all that relies on some understanding of physics. In each case, it was a breakthrough in physics that allowed us to create some new technology to connect our computers together. Well, let's talk about fiber optics. As you say, fiber optics are crucial for sending information across the oceans or even just around your neighborhood. Like in my neighborhood, it's all fiber optics that connects houses to houses and to those backbones. And that's because it's very robust. Having fiber optics requires optics and then also requires lasers to send pulses down those fiber optics. You need like tiny little mini lasers which rely again on quantum mechanical principles to send those pulses down these crazy glass tubes. And that's where lasers are super important. The physics of lasers is also fundamentally quantum mechanical. Again, you have some kind of atom with specific energy levels. That's quantum mechanics, and these atoms can emit and absorb specific frequencies of light. And then if you add a pumping source that can excite the atoms to some high energy state so they emit that light and for the whole thing in a cavity that has a resonance at that frequency of light, then you get the laser effect self oscillating because of all that optical feedback. That's super cool because you can get a coherent beam of light, one that has only one frequency and is super collimated. That's perfect for optical communications.
Yeah. Interesting, Although as an engineer, Daniel, I just feel like I have to plug think the plug for engineers, Like, I wonder if you dig into the history of it like that, maybe the person who first started using lasers for communications, or the person to figure out you can make fiber optics. Like I wonder if you can actually drill down and say, oh, the person who came up with that idea was an optical engineer, not actually a physicist, or like a materials engineer, not actually a physicist, although obviously engineers are all trained in physics to some degree.
Yeah, you know, I'm not a big fan of drawing dotted life lies between groups of people and putting labels on them. In the end, it's just smart people being curious and trying to make new stuff. In the case of the laser, I think it really was driven by physicists. You know. It's like Charles Towns thought about the maser first, and then later on people developed into a laser. And this is all research down at Bell Labs and at Berkeley, and these are academic physicists that invented these ideas for the laser. At least in the case of fiber optics, I think there's definitely a lot of engineering that goes into that. You know, you might have the basic principle from physics, but then actually making these fibers that like go for miles and miles without losses is really pretty impressive amount of engineering. So it's definitely, you know, a beautiful duet of skills.
All right.
Yeah, So, like you said lasers and optics, there's also like radio ways, right, we use radio ways to communicate as well.
Yeah, most people who are listening to us right now are probably receiving that information not through wired communications but wireless communication. And back in the day, radio is the breakthrough that allowed us to communicate across oceans and to receive music in your house in your radio. But these days even just Wi fi is essentially an extension of radio. We're sending information via electromagnetic radiation.
Yeah, it's pretty wild, right, Like Wi fi is such a common household word, my kids use it all the time. But really you're talking about radio ways being shot everywhere all around.
Us, Yeah, exactly. And to orient you radio waves on your FM dial, for example, those are like eighty eight or up to like rockin one o eight or whatever. Those are all megahertz frequencies. So you know, ninety three point seven means ninety three point seven megahertz. That's the frequency of the radio wave that's being used to transmit you information. But that's just the frequency of the light. If the frequency was in another range, it would be visible light that you could see it. If it was in a different range, it would be Wi Fi. So Wi Fi is in like two and a half gigahertz or these days the five Gene networks are five gigaherts, so much higher frequency, but still basically radio waves.
Yeah.
I always wonder, like what if our eyes could somehow see radio ways or see like a different range of frequencies of light, Like would we'd just be walking around with like bright lights and pulsing lights everywhere all around this.
It's sort of amazing. We can only see a tiny slice of the spectrum. Of course, the slice that we can see happens to be also the most common kind of light. Our ability to see light peaks where the sun is the brightest, so that's not a coincidence. But there are other species out there with the capacity to see light into the UV or down into the infrared, so it's not like only humans that can see things obviously.
Yeah, But like if you could see light in that frequency, you would hold up your phone and sometimes it would glow a little bit more or start pulsing a little bit more than when it's sending these signals.
Out exactly. And when we look out into the universe, we have infrared telescopes, we have X ray telescopes, we have UV telescopes, and they all see different things out there in the night sky. The night sky looks very different in the infrared as it does in visible light or it does in the UV. So if we have the ability to see those things, we would see lots of other stuff going on all the time, and then we might give a second thought to like filling our world with these waves. We wouldn't build a communication system that relied on flashing visible light everywhere. That would just drive people crazy. So it's sort of an advantage that it's not visible to us, because then we can use it to invisibly send information.
Yeah, I guess if you had the idea to make your cell phone work using visible light, it would be kind of a terrible idea. I mean, you'd be basically doing like a Morse code between ships.
But there's also a lot of clever engineering in making like cellular phones work. Wi Fi is one thing. It's a certain band of information with cell phones work and different frequencies, and there's a lot of really clever ideas to making your cell phone work.
Well, maybe can you talk about like how the antenna in my cell phone works, Like, is it like a little tiny flashlight that just emits light at a certain frequency, or is it more like the traditional radio antennants.
It's more like a traditional radio antenna. Basically, the way you emit electromagnetic radiation hasn't changed. You take a bunch of electrons, you wiggle them back and forth, and wiggling electrons makes wiggles in the electromagnetic field. Because information takes time to propagate. You move an electron up, the field changes, but not instantly at a distance. So you move it up and down, up and down, up and down. Then the electric field is changing, and it is changing up and down, up and down, up and down. And so that's basically how you create electromagnetic radiation. You wiggle it a fast frequency, you get high frequency radiation. You wiggle it slowly you get low frequency radiation. That's the way you generate electromagnetic radiation in your antenna. That's also the way you can receive it. You got electrons in the antenna, they are wiggled by incoming radiation. You detect that and you pick.
Up the signal it seems almost very primitive, right.
Yes, it's sort of old school.
M all right, Well, let's get into some of the other technologies in your cell phone and how those depend and maybe not depend on physics and or engineers.
So it's doodad, But first, let's take a quick break.
When you pop a piece of cheese into your mouth, or enjoy a rich spoonful of Greek yogurt, you're probably not thinking about the environmental impact of each and every bite. But the people in the dairy industry are. US Dairy has set themselves some ambitious sustainability goals, including being greenhouse gas neutral by twenty to fifty. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. Take water, for example, most dairy farms reuse water up to four times the same water cools the milk, cleans equipment, washes the barn, and irrigates the crops. How is US dairy tackling greenhouse gases? Many farms use anaerobic digestors that turn the methane from maneuver into renewable energy that can power farms, towns, and electric cars. So the next time you grab a slice of pizza or lick an ice cream cone, know that dairy farmers and processors around the country are using the latest practices and innovations to provide the nutrient dense dairy products we love with less of an impact. Visit usdairy dot com slash sustainability to learn more.
There are chiltern friends and families walking, riding on paths and roads every day. Remember they're real people with loved ones who need them to get home safely. Protect our cyclists and pedestrians because they're people too.
Go safely.
California from the California Office of Traffic Safety and Caltrans.
Want the secret to your best skin yet. I've been getting a ton of compliments on my skin lately, and the secret Biosance, this award winning skincare brand known for its science backed formulas, has been a game changer for me. The best my skin has ever looked is right after I started using these two holy grails, the Biosance Omega Repair moisturizing cream and Marine Algai cream. These are just my personal faves. They're clinically proven products that deliver real results. Clinical trials have shown that one percent of Omega Repair moisturizing cream users sawn increase in skin hydration after five minutes. And if you're concerned about fine lines like me, the Marine Algai cream users saun ninety seven percent improvement in the appearance of fine lines and wrinkles after one use. Are you ready for your best skin ever? Head tobiosons dot com and discover your next skincare obsession. And by the way, use code POD that's Pod at checkout to score an exclusive surprise gift with any order that's code POD at checkout.
Have you made the switch to Nix? Millions of women have made the switch to the revolutionary period underwear from Nix. That's k Nix. Period panties from Knicks are like no other, making them the number one leakproof underwear brand in North America. Their comfy, stylish, and absorbent perfect for period protection from your lightest to your heaviest days. They look, feel and machine wash just like regular underwear, but feature incognito protection that has you covered. You can shop sizes from extra small to four XL choose from all kinds of colors, prints, and different styles from bikinis to boy shorts. Thongs to high rise. You've got to try next. See why millions are ditching disposable, wasteful period products and have switched to Next. Go to knix dot com and get fifteen percent off with promo code try fifteen. That's nix dot com. Promo code try fifteen for fifteen percent off life changing period underwear. That's k nix dot com.
All right, we're talking about the physics of the Internet, and now specifically about the physics in your cell phone. We talked about the antennas and how Wi Fi works, but there's also other interesting physics in other parts of your cell phone.
Yeah, WiFi is a certain frequency, and you know how your phone can be connected to your house Wi Fi. Then you get all sorts of good stuff at very high speeds. But then when you're out and about and there isn't Wi Fi, you can connect to your cell phone data network and it's a completely different way to receive information that relies on the same physical principles. It's still basically radio packets, though it's at a different frequency. So whereas Wi Fi is like two and a half or five gigaherts, cell phones receive data like nine hundred megahertz ish, but as you're walking around, they do something that seems kind of magical. Like you walk down the street, you're chatting with your friend, You're getting further and further away from that antenna that's sending you information and receiving information. All of a sudden, you're closer to another antenna and you don't even notice, You don't even care, you're watching that cat video or talking to your friend. It just is all smooth and seamless. That's accomplished through a lot of really clever engineering to hand that call off from one tower to the next tower.
Now, can you explain, Daniel, what in these cell phone companies, what do they mean by like five G seven G LTE is at all different physical technologies like higher, faster, more accurate, or is it just like the protocols are getting more sophisticated.
Five G means fifth generation and so in some senses, like a change in the underlying technology that we're using. It's a change in the frequency of that radiation we're using to go from like three D to four G or LTE is a change in the protocols, like how they're handing them off from one to the other. How they're building that information into the packets that get sent back and forth between the phone and the tower. So that's all engineering.
Well, it's all engineering.
It's not just then sort of our antenna and our radio ways. There's also other interesting physics in your phone, like even just like how your phone knows which way you're holding it.
Yeah, your phone can do something pretty cool, which is can measure your location. But it could also, for example, measure your acceleration. So there's two things there that your phone can do. One is it could sense its direction. It's got like a little tiny gyroscope in it. But also it's got accelerometer, so it can measure basically whether you were speeding up or slowing down. You know, fundamentally, the principle of relativity says you can't measure your velocity. There's no absolute velocity. So if you're on a train, or if you're standing on the ground, or if you're an airplane, your phone can't tell I mean other than like measuring your location using GPS. But just on the phone, it can tell if you're accelerating. It can tell if you're speeding up. You can tell if you're slowing down. It can tell if you're like crashed, because that's a moment of severe deceleration. And to do that it uses a very old school kind of physics sensor.
Right.
It's just basically like a weight at the end of a spring.
Yeah, exactly. Like if you were in the back of a pickup truck and you had a bowling ball. You could tell when the person hit the gas because the bowling ball would roll towards the back of the truck, And you could tell when they hit the brake because the bowling ball would roll towards the front of the truck. So all you need is some sort of mass and for it to be not connected to the rest of the truck or in this case of the phone. So inside your phone they have something that's kind of like that. It's not a bowling ball, but it's a big block of metal. It's basically balanced on a very fragile spring, and when you accelerate your phone, that metal is like left behind a little bit and when you break that metal keeps going a little bit, and inside the accelerometer it measures the position of this slab of metal relative to the rest of the circuit board, and so it can tell when you're accelerating. So if you like shake your phone, it can tell that you're shaking your phone in frustration.
Right, But it's not just shaking like dune. Cell phones also use accelerometers to measure the direction of gravity and to tell which ways up and down and whether you're holding your phone like horizontally or vertically.
They use xilometers for that, right.
Yeah, And principle, you could measure the gravity of the Earth because that's basically an accelerometer. If you jumped off a building, you'd be in free fall. There's no gravity for you to measure. You just naturally following the curvature or space and time. But if you're standing on the Earth, the Earth is pushing you up against your natural inclination to follow that curvature, and that's acceleration. And so what you actually measure at gravity on the surface of the Earth is really the acceleration of the surface of the Earth relative to the natural motion in curved space.
Pretty cool.
And you also made me think of your GPS and your phone also requires basically a special or general relativity to make that work, right.
Yeah. The network of satellites that tell you where you are and where you can go to get your boba or whatever. Those are very precise locations. You get messages from those satellites, and your phone reconstructs your location based on the pulses and the information in those satellites, and they have to be very, very precise in order for you to have precise timing information. And those things are moving far above the surface of the Earth where time flows differently because space is not as curved in their orbits as it is down here on Earth. If you don't account for that in all of your calculations, then all the clocks get out of sync and you don't make it to your Bobo store before it closes.
Which I know is a primary concern of yours at all times. D Daniel, You're always trying to get that boob. Yeah, it's like they try to make GPS work, but it didn't work, and then they realized they needed to take into account like the curvature of space around the Earth, right, and the way that time slows down for things that are closer to Earth and further away from Earth.
Right.
Yeah, exactly, Clocks on the surface of the Earth run more slowly because we are deeper in a gravitational well there's a greater curvature of space and time here on the surface of the Earth than there is up in orbit in space where the curvature is less, and so time runs more naturally, it runs faster, So you got to take that into account.
Yeah, and then I guess the last category is sort of like a power in your cell phone that also requires a lot of physics.
Yeah, if you build a computer, then it requires power. You know that you've got to plug it into the wall. And if you're running a bitcoin farm somewhere, of course, then you know it takes a significant amount of power to do computation. And in the end, this comes down to thermodynamics, which of course is a fundamental part of physics. Essentially, if you I have a computer, doing computation means changing the state. You want to flip a bit from zero to one, you want to change a circuit. Anytime you do that, anytime you change the configuration of an object that's doing work that requires moving something. It takes energy to flip a bit, or to move those electrons to create the conduction channels inside your transistor. All that stuff takes energy, which means it's always, always, always going to generate waste heat. That's what thereodynamics tells us that you can't do anything without creating waste heat. And silicon wait first, when they're doing computation, generate a lot of heat. So you know, like one hundred watts boils off of a silicon chip as it's cooking, as it's doing its thing. And so it takes a lot of power to do computation. And one thing that the Internet has enabled specifically is not just putting a bunch of computers on the Internet, so you can send stuff back and forth to each other, but you can do computing remotely. If I have a calculation I want to do, I don't need to do it on my comput I can send it to a bunch of computers up at Berkeley or down at Livermore or somewhere else. Basically cloud computing. Amazon has these huge data centers filled with computers that people can use at a moment's notice because the Internet basically means that they're right there with us. That also means that it's simpler to have access to vast quantities of computing. You don't have to build your own computing center to have a lot of computing power. And that's become very, very popular. I use it in my research all the time. CERN for example, has an enormous set of computers all around the world that work together to solve problems. But as these computer centers get bigger and bigger, of course they draw more and more power. Projections suggest that these data centers are going to keep sucking energy, and it's going to keep growing. The networks, of course, also use energy. It's not just like free to send information down a wire. You've got to create a pulse that's power, that takes energy. One projection I read suggested that by twenty thirty, more than twenty percent of all electricity demand will come from the internet, data centers, consumer devices. Production of these things, like actually building these things takes energy, and then just running the networks altogether, these things are going to take more than twenty percent of our energy budget. It's dominated by the networks and by the data centers. You also got to spend energy to cool these things, like they are generating waste heat, which means that they're using power. But then you also need to keep them cool because they melt themselves down. They're no longer going to be able to do any computation. So there's like air cooling and water cooling, and that involves again more heat transfer and more power, which takes more energy. So all this stuff is not free. The Internet costs a lot of power, and as we move into a future where using power has significant consequences for our climate and for our globe, we got to make sure we're not just like spending a huge amount of power to make CAFOs. So there's real consequences there. A very important part of the Internet, and understanding how that works in the end comes down to the basic thermodynamics of how computing really works.
All right, Well, I guess that's another interesting reminder that there's physics everywhere, including on the thing that probably most humans use nowadays the most.
That's right, physics has enabled all of your goofing.
Off physics and engineering.
Physics has sort of shot itself in the foot. It's so effective at building communication networks and new technology to connect us that now we're all so distractable.
Although if you asked me, as some of you might know, I am a big fan of distractions for a creative thinking, So in a way, maybe the Internet has helped the creatuty also.
Physics is powering your procrastination, that's what you're saying.
Yes, yes, I have physics to blame and engineering to think.
Would you say you're a procrastination engineer or procrastination artist?
I'm a procrastination in gen artists. All right?
Well, again, just a fun reminder to keep your eyes open because there are interesting things to discover and to explore and to find the science of in our everyday lives.
That's right. And remember that as we understand the universe better and better, we can develop new technologies which then help us understand the universe better and better. So physics is cyclical.
Yep, as is engineering. Right.
Well, we hope you enjoyed that. Thanks for joining us. See you next time.
For more science and curiosity, come find us on social media where we answer questions and post videos. We're on Twitter, Discord, Instant, and now TikTok. Thanks for listening, and remember that Daniel and Jorge Explain the Universe is a production of iHeartRadio. For more podcasts from iHeart Radio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen into your favorite shows. When you pop a piece of cheese into your mouth, You're probably not thinking about the environmental impact, but the people in the dairy industry are. That's why they're working hard every day to find new ways to reduce waste, conserve natural resources, and drive down greenhouse gas emissions. House US dairy tackling greenhouse gases. Many farms use anaerobic digestors to turn the methane from manure into renewable energy that can power farms, towns, and electric cars. Visit you as dairy dot COM's last sustainability to learn more.
VitaminWater was born in New York because New York is wanted more like more flavor to go with all the flavor, a refreshing drink after climbing six flights of stairs to a walk up apartment or standing in the subway station in a hundred degree heat drink. Vitamin Water is from New York.
There are children, friends, and families walking, riding on passing the roads every day. Remember they are real people with loved ones who need them to.
Get home safely.
Protect oursel anclists and pedestrians because they're people too.
Go safely.
California from the California Office of Traffic Safety and Caltrans
