Pod Insights a16z Podcast From Big Bang to James Webb: Exploring Space with Nobel Laureate John Mather About this episode From artificial limbs to memory foam, many inventions have emerged from our quest to understand the cosmos.
In this episode we explore cosmic history, space's impact on technology, and the enduring human fascination with space exploration. To take us on this journey is astrophysicist John Mather, a Nobel Prize winner for his work on the COBE satellite and a key figure in the James Webb Space Telescope project.
Prepare to be intrigued and left with a sense of wonder about the universe's influence on our world.
Transcript Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
0:00 Speaker 00 Right now, we still have the great mystery of quantum mechanics doesn't seem to describe gravity. Can we find places that are like home? Little Earths orbiting stars like the sun. When you look at the history of Earth, you see the history of the different forms of life growing. It's taken all of the entire history of the universe for us to turn up. We start off with, "That can't be done, that's impossible." Then somebody invents something, and then somebody wants some more. And gradually, we invest our billions or trillions, as it takes, because there's a demand for it. Please build us another telescope to look farther back, because we've got a big mystery here.
0:40 Steph Smith? Artificial limbs, precision GPS, firefighter suits, insulin pumps, emergency blankets, air purifiers, even the dust buster. Now, what do all of these things have in common? Well, these were actually all innovations developed through the pursuit of space. And I think there's something really profound there. Through our collective deep desire to understand our past and all that we came from, we've created technologies that enhance our future. I think it's also an important reminder that history is riddled with people who think they know what is best to build, without realizing that there are so many great things that have sprouted from projects
1:25 Steph Smith? that didn't seem immediately useful at the time. And that's why today I am so excited about our guest, astrophysicist John Mather. Now, John actually won the Nobel Prize in Physics in 2006 for his work on the COBE satellite. To which, by the way, Stephen Hawking described the imagery from COBE and its implications on the Big Bang Theory as "the most important discovery of the century, if not all time."
1:56 Steph Smith? More recently, John was a senior project scientist for the James Webb Space Telescope, and that was the feat of science that produced the images of those far-out galaxies that you probably saw as the Biden administration revealed them in the last year. Now, this episode came about because I had the pleasure of seeing John speak at the Aspen Ideas Festival, and after his talk, I had to ask him, I had to shoot my shot, to see if he'd come on the A16Z podcast. And in this complex world of cosmic probabilities, John actually said yes. So here we are, venturing into the very beginnings of our cosmic history. We also talk about what we've learned in the several decades that John has been working
2:40 Steph Smith? in this space, but also the many things that we have yet to understand, so things like dark energy and dark matter. Plus, we explore the very important question of why space exploration is such a fundamental but also useful human desire in the first place. And given that the James Webb Space Telescope that John has been working on recently made its first detection of a new carbon compound, methyl cation, this conversation is all the more timely. In the best way possible, I think this is one of those episodes that may leave you with more questions than answers, but I hope you enjoy it as much as I did.
3:22 Steph Smith? As a reminder, the content here is for informational purposes only, should not be taken as legal, business, tax, or investment advice, or be used to evaluate any investment or security, and is not directed at any investors or potential investors in any A16Z fund. Please note that A16Z and its affiliates may also maintain investments in the companies discussed in this podcast. For more details, including a link to our investments, please see a16z.com/disclosures.
3:52 Steph Smith? Maybe we could just go back to when you started exploring this concept of space and the work that you've done. What was our understanding at that time?
4:01 Speaker 00 Oh, my goodness. Well, you're asking me to jump back when I was born, which is 76 years ago. And in 1946, hardly anything was known about what we currently can tell you. We had just finished up a war. We had learned a lot about physics because we invented all kinds of new weapons, including radar and atomic weapons and things like that. So we had realized that rocketry was possible. So then we, scientists, got busy and we discovered the most astonishing things. We found out the physics of the universe a lot. We've uncovered the nature of the particles. We've learned about quantum mechanics. Then the space age came along, partly because it was tied to weaponry. So we invented space travel.
4:46 Speaker 00 In 1957, the Soviet Union launched a little Sputnik. Suddenly, the government realized we better invest in science and engineering.
4:54 Steph Smith? Yes.
4:55 Speaker 00 They played Jack Kennedy's talk announcing that we were going to go to the moon, not because it's easy, but because it was hard. And he also promised that we would do the other things, too. And what he had in mind, I'm not sure exactly, but we were clearly up against medical issues and cultural issues. And we still had the remnants of slavery very strongly in our country. There was segregation and legalized mistreatment of a good portion of our country. And so he knew that that was a big set of things to work on, too. And he's promised we would do them all. So that was pretty brave, and we're still working on a lot of them.
5:29 Steph Smith? We are.
5:30 Speaker 00 Because some things are harder even than space engineering.
5:33 Steph Smith? Tell us about when you started getting involved in this.
5:36 Speaker 00 Well, I got interested pretty young. I think I was about six years old.
5:41 Steph Smith? Wow.
5:42 Speaker 00 I heard from my dad at bedtime, story time, that living things are made out of cells with chromosomes. And this was before we even knew about the double helix. So, okay.
5:51 Steph Smith? That's right.
5:52 Speaker 00 That got my attention. My friends and neighbors were farmers. My dad was studying dairy cows.
5:57 Steph Smith? Wow.
5:57 Speaker 00 For his research for Rutgers University. And so that was where I got started.
6:02 Steph Smith? Yeah.
6:03 Speaker 00 Living out on the farm, thinking about deep things like that, the origin of everything. If you know about cells and chromosomes, then immediately you understand evolution and the huge changes that can happen through time. I think I was about eight. We went to see the Museum of Natural History in New York and the planetarium show and the giant meteorite, sitting there, as big as a small apartment, just sitting there. You say, where does that come from?
6:28 Steph Smith? Where do we come from?
6:29 Speaker 00 And where do we come from? So you see the bones arranged and showing evolutionary order in the museum. Oh, my golly, what a fascinating story. I want to know everything about this.
6:38 Steph Smith? Yes, yes. And we didn't know that much about space at that time. Maybe I'm getting a little too ahead of myself because I'm sure there's so many years between what you're describing and when you won your Nobel Prize. But that did seem like maybe the start of a new era of our understanding of space. And so could you speak a little more to the satellite that you had developed with your partner?
7:00 Speaker 00 Yeah, sure.
7:01 Steph Smith? And what that really meant as maybe an inflection point?
7:03 Speaker 00 So back in 1970, I was in graduate school at the University of California, Berkeley, looking for a thesis project because I was tired of studying in the library and maybe I better build something. So the people had just discovered the cosmic microwave background radiation.
7:18 Steph Smith? Okay.
7:18 Speaker 00 It is thought to be the remnant of the early universe. The hot big bang still fills the universe. And so can a graduate student do something to go measure it better? So the answer is yes, we'll try something. So, okay, well, I worked on a project which was an instrument to measure the spectrum, which is to say, how bright is this radiation at each different wavelength?
7:40 Steph Smith? Yep.
7:41 Speaker 00 And we built it and we sent it up, attached to a high altitude balloon. And it went up and it did not work. Oh, man, what do I do now? So my thesis advisor said, OK, well, you did good work. You can write this up and you can make a thesis out of it. They've already published some other papers. So I said, OK, I'll get a job. I got a job for NASA. Five years before that, we had just landed on the moon for the first time.
8:03 Steph Smith? Wow, OK.
8:05 Speaker 00 So, OK, 1974, I'm at NASA Laboratory in New York City. And, OK, so NASA puts out this announcement of opportunity, calling for new satellite missions for science. Because what are we going to do after the moon landings are done? Maybe do something else.
8:20 Steph Smith? Yeah.
8:21 Speaker 00 Because we can't keep on going to the moon all the time. So, OK, boss, my thesis project failed. We should try it in outer space. So I had no idea how much nerve was required to do this. So we just did it. We wrote a little thin proposal. We said we have an idea. So after a couple of years, NASA said, well, we think it's a good idea. And I got a job at the big NASA laboratory in Greenbelt, Maryland, just outside Washington. And they gave us some engineering time to work with people who knew how to build stuff in space. And, well, in 1989, it went up.
8:52 Steph Smith? It did?
8:53 Speaker 00 And it worked.
8:53 Steph Smith? Wow.
8:54 Speaker 00 And within weeks, we had measured the spectrum. My thesis project that had failed as a balled payload now worked beautifully in outer space.
9:03 Steph Smith? That's incredible.
9:04 Speaker 00 I showed a graph to the Astronomy Society, and we got a standing ovation for a graph. And so they knew what it meant. They knew, basically, that not only was the equipment working, but the story of the hot Big Bang was basically right. People don't remember now that there used to be alternate theories that said, well, maybe it wasn't so. A couple of years after that first announcement, we were able to say, we made a map of this cosmic heat. And our map showed pink and blue blobs across the entire sky. And what they show is, if you could see millimeter waves with your eyes, you would see this big fuzzy map. And it's not, it's very blurry. But it was enough to say, the early universe was not the same everywhere. There were hot and cold spots. And that matters to us, because if the universe
9:49 Speaker 00 had been completely exactly uniform, gravity wouldn't know what to do. It would not have any way to pull material back together again, to stop the expansion locally, and make galaxies and stars and planets and people. So we're here because of those spots. And so that's pretty revolutionary.
10:06 Steph Smith? That is.
10:07 Speaker 00 It used to be people looked at this amazing universe and thought, it requires divine intervention because it's too darn complicated. Nobody could possibly see how it could work. We confuse, I don't know how it works.
10:19 Steph Smith? Yes.
10:19 Speaker 00 Or I don't know how to do it.
10:20 Steph Smith? Mm-hmm.
10:20 Speaker 00 With, it can't be done, or it's impossible. When it comes back to, how did we get here? It used to be, we couldn't understand how to calculate anything. So we figured, it must be impossible. It must require divine intervention. And now I think we have a different picture.
10:36 Steph Smith? Yeah.
10:36 Speaker 00 I may divert into that a little bit, because, how is it that nature spontaneously produces complicated stuff?
10:42 Steph Smith? Yeah.
10:43 Speaker 00 So, there are reasons. There are fundamental, deep reasons why nature produces complicated stuff.
10:48 Steph Smith? Mm-hmm.
10:49 Speaker 00 So, when you think of nature as just full of atoms, and atoms are just little billiard balls, and they have no shapes and no properties, then of course, it would be extremely unusual for them to stick together and form what they do. But quantum mechanics says, no, atoms are not little billiard balls. They have shapes, and they're like covered with Velcro of different flavors. So atoms stick together in certain patterns, because that's how nature is. So, okay, then, also we know about thermodynamics, which tells us which kinds of reactions are favored by nature.
11:21 Steph Smith? Yes.
11:21 Speaker 00 So if energy is released when two atoms come together, then it's likely to happen.
11:25 Steph Smith? Mm-hmm.
11:25 Speaker 00 So now we say, okay, it's not completely without pattern. Nature gives patterns because of quantum mechanics and thermodynamics. So, it's just built in that complicated things will occur, given a chance.
11:39 Steph Smith? Yeah.
11:39 Speaker 00 So, okay, the universe spontaneously heats up. This is something they don't teach you in school. In school, they say, well, nature does not have two objects just sit there at the same temperature, and one gets hot and one gets cold. That's true in normal life. But gravity is an exception to that.
11:55 Steph Smith? Okay.
11:56 Speaker 00 So, this is pretty deep and fundamental. Gravity is the reason why the universe has heated itself up. Gravity can stop the expansion of the material of the big bang, and pull it back in to make stars. Then when it does that, the stars can light up. And release nuclear energy. And now we have a state of the universe where it's hot in some places and cold in other places. So, energy flows from place to place. And this is then the basis of the complexity that we now have.
12:23 Steph Smith? Yeah. And that's partially what we got from, you're saying, this image. Because if this wasn't the case, if you're saying gravity didn't exist and create these local changes, then what would we see? Would we instead have seen just a clean image?
12:36 Speaker 00 Yeah. If gravity could not have acted on those hot and cold spots, those dense and less dense regions, then nothing would have happened. It would just have been a completely featureless expanding universe with no stars, no galaxies, no anythings.
12:50 Steph Smith? Yeah.
12:51 Speaker 00 All the same temperature, completely boring as far as we're concerned, we wouldn't be here.
12:55 Steph Smith? We wouldn't be here.
12:56 Speaker 00 But nature does have gravity. Nature does have the other three forces of physics. And it does have quantum mechanics and thermodynamics. And so, it's just designed in some way, if, oh, that's not really the right word. It is a universe in which complexity naturally appears.
13:11 Steph Smith? Yeah. And maybe you could just speak to what a phase change, again, this was in our understanding. Because I think even Stephen Hawking said this maybe was one of the most important images to come through science about, you know, maybe, I wasn't sure if he was referring to it in terms of just our cosmic understanding or our understanding of the whole world. But, yeah, why was this such an important discovery?
13:33 Speaker 00 Okay. Well, Stephen Hawking looked at our map of the pink and blue blobs and he said it was the most important scientific discovery of the century.
13:40 Steph Smith? There you go.
13:41 Speaker 00 If not of all time. And I first thought, oh, Stephen, you're just exaggerating. But it's very nice. And then I thought, okay, well, in truth, if we could understand where those spots come from, it would tell us perhaps about the unification of the forces of nature. Right now, we still have the great mystery of quantum mechanics doesn't seem to describe gravity. But we-
14:02 Steph Smith? We know it exists.
14:03 Speaker 00 Have the opinion that it ought to.
14:04 Steph Smith? Yeah.
14:05 Speaker 00 And if it does, then it means that even space and time are randomly fluctuating and weird. And so that was, it's like one of the great mysteries of science. And we think there ought to be something there. Scientists have been working at least 50, maybe 100 years trying to figure out how gravitability and quantum mechanics should go together. The other thing, of course, is where did we come from? And if those spots weren't there, then we wouldn't be here. So that's pretty cool. And it even tells us through detailed analysis that there is something called cosmic dark matter, which we can't see and perhaps never will see. So we've got all these wonderful mysteries that are all embedded in this map of pink and blue blobs.
14:46 Steph Smith? Yes.
14:47 Speaker 00 And so it's totally fascinating and draws in thousands and thousands of scientists. Since the COBE satellite was flown, two more satellites were built and flown, and they confirmed our original measurements, which is nice because that meant we could get a Nobel Prize for discovering the thing that turned out to be true. What if it weren't true? Then, of course, you don't get a prize. But now we have much, much more detail to go on.
15:10 Steph Smith? Let's talk about that, right? So you were the lead project scientist or senior project scientist on the James Webb Space Telescope. And I feel like that was the most recent exposure that the everyday person had to the frontier that we're now approaching.
15:28 Speaker 00 After the Hubble telescope was launched, scientists said how wonderful it was.
15:33 Steph Smith? Yes.
15:34 Speaker 00 And by the way, we still can't tell how the galaxies grew. And it was still one of the great mysteries of science because we thought we would understand. We thought, oh, now we know about the big bang and the hot and cold spots, and we should be able to simulate and calculate how galaxies would grow. And then we measured with the Hubble telescope, and we got it wrong. The predictions had been that galaxies would grow slowly. So the Hubble would be able to see the first ones happening. And of course, how do you see that? Well, you see back in time by looking at things that are far away. So you've got your own time machine in your eyeballs every morning, but you don't feel it.
16:11 Steph Smith? Yes.
16:11 Speaker 00 So look back in time, see what the universe's like when it was young, and see what were the galaxies doing? And they were already pretty grown up as far as back in time as the Hubble could see. So please build us another telescope to look farther back because we've got a big mystery here. So we still have a big mystery because we built the Webb Telescope. It did what it was supposed to do. It produced beautiful pictures. And right away, we could see that the galaxies grew even faster than we thought. And so even though we had the information from Hubble and all the simulations and calculations and predictions, we were still wrong. So we're looking for something really deep and fundamental. Don't know what it is.
16:52 Speaker 00 So that's why astronomers are thrilled right now that they've got something to work on. And it's going to take us a good, long time, could be decades, before we really deeply understand what were we wrong about. And it's even possible that there's some new force of nature or some thing that happened early on that's just so different that we can't even imagine it yet.
17:12 Steph Smith? Why don't we actually look at some of these images from James Webb?
17:16 Speaker 00 Okay. So we have something that Joe Biden released at the White House on July 11th last year. And it shows quite a few remarkable things. There's some stars with six legs sticking out. And that's just due to the wave nature of light because light sort of bends around the hexagonal edges of our mirrors. But we knew about that. So stars are not that exciting right now. Then in the middle of the picture are some giant fuzzy galaxies, enormously massive. And we sort of knew they were there already. And so that wasn't so exciting, but we wanted to know exactly how massive and exactly where all that stuff is. And then in the background, our little pink arcs, curved things that do not look like galaxies, but they really are.
17:59 Speaker 00 And so they are highly magnified and distorted images of very distant objects. And nature has given us lenses, extra lenses in space, to magnify the more distant universe. And this is something that Einstein predicted. And we never thought it would be useful, except in a most abstract way. So now what we see is sometimes two, or three, or four, or five images of the same distant object, all stretched out and magnified. So this is a way to look farther back in time, to see the details of the very first galaxies. So that's the coolest thing for the astronomer in that picture. So sometimes we even see that the early galaxy is filled up with little sparkly things.
18:42 Speaker 00 We call them globular clusters, like 100,000 stars that were presumably formed together. And now our big question is, well, which came first, galaxies or globular clusters? Did the universe make the little clusters first and then they joined together? Or did the galaxy form first and then break up into little clusters? So this is one of our generic questions of which came first, chickens or eggs? Or breadfruit? I don't know. Which brings me to another question about early galaxies. There's a black hole, giant black hole in every galaxy, just about.
19:14 Steph Smith? Yes.
19:15 Speaker 00 And so we know they're there because we see things orbiting around them. So we calculate that there's something, immensely massive object in the middle. Sometimes they're very bright because material is falling in and getting compressed to enormous temperatures, and we can see that part. And now we want to know, well, which came first, the galaxy or the black hole? Did the universe start off with black holes all over the place? Or did it make galaxies first and then they made the black holes? So we've begun to observe black holes out there. We've even seen a few years ago, black holes colliding with each other and joining together to make bigger black holes.
19:49 Steph Smith? This is with the James Webb?
19:50 Speaker 00 That was done with the LIGO Observatory, which is here on the ground. And we've even more remarkably seen neutron stars colliding and making a bigger neutron star. And that has its own story to tell. Because, for instance, when you look at your ring, if you have a wedding ring of gold, then we know that most of the gold in that wedding ring came from neutron stars that collided and blew up and material came back out into space and was recycled. So this is a part of the most astonishing story about our own origins, that we're made out of not only recycled stars, but neutron stars that collided and blew up. And so our own personal story is-
20:30 Steph Smith? Our ancestry.
20:31 Speaker 00 -got the most remarkable threads in it.
20:32 Steph Smith? I just want to ask you about this particular image, which has been referenced a lot in terms of understanding exoplanets and the composition of them. And perhaps you could speak to maybe what we've learned there and also what it may indicate in terms of life that we have maybe come across, not come across. I think the answer is the latter, but also what that maybe opens up for the future.
20:53 Speaker 00 Yeah, sure. So yeah, everybody wants to know, are we alone?
20:57 Steph Smith? Yes.
20:58 Speaker 00 And if we're not alone, where are the neighbors? So I'll jump ahead to what I think the answer is. I think the answer is no, we're not alone. And I think life will occur quite frequently, but it will mostly be rather elementary. And when you look at the history of Earth, you see the history of the different forms of life growing. It's taken all of the entire history of the universe for us to turn up. So that does tell us that we're kind of rare in history. So probably life is everywhere that it could be, which is perhaps in conditions like ours, where there's liquid water at about the right temperature. But probably we're not going to find the neighbors. Similarly, that we're not in danger from the neighbors. So maybe we got lots of unexplained things here
21:42 Speaker 00 on planet Earth, but it's not very likely to be space aliens.
21:45 Steph Smith? Yeah.
21:45 Speaker 00 Something else that we don't understand instead. So what are we going to do about measuring? Well, of course, here in the solar system, we're sending out probes to land on Mars and visit other places where there could be life and see. So on Mars, we're working to bring back little rocks that have the chance of having fossils in them. So that's really hard, but we're working on it. We're already putting the rocks in little caches to get ready to bring them home.
22:11 Steph Smith? Yeah.
22:11 Speaker 00 We are sending probes out to orbit around satellites of Jupiter and Saturn, where water is coming out. There are places where there's a liquid water ocean covered with ice. And there are cracks in the ice and the water comes out and you can see something. And so for lucky, we might find out there are organic molecules in those oceans.
22:32 Steph Smith? Fascinating.
22:32 Speaker 00 I would say maybe there's life under there. And so it gives us impetus to track it down and find out more. So then we get to what can we do about other planets, around other stars? Can we find places that are like home? Little Earths orbiting stars like the Sun. So far, we don't know of any like that because it's a really hard observational problem. What we're doing at the web, we are looking at planets orbiting smaller stars that are called M stars. So these are very weak little stars that are hardly as big as Jupiter, but they're warm enough to-
23:05 Steph Smith? Hardly as big as Jupiter. It's just funny with our sizes, tiny little humans.
23:10 Speaker 00 As a matter of scale, Earth is 8,000 miles across, Jupiter's 88,000 miles across, and the Sun is about a million miles across.
23:17 Steph Smith? It's good framing, good reference.
23:18 Speaker 00 Roughly each one is 10 times bigger than the other. So yes, we're able to study planets around small stars because some of the time, the little planet will go in front of the star and it'll block some starlight. So, okay, now we know it's there. We can calculate its temperature and its size and whether it possibly hosts an ocean. Okay, now, does it have an atmosphere? So, yes, maybe. So, look to see if any of the starlights going through the atmosphere of the planet on its way to the telescope. And, yeah, we can do this. And we have a pretty large catalog of large planets that do have an atmosphere with interesting molecules in them. And so the technique works. And now we're just now busy analyzing the small stars that have potentially small
24:03 Speaker 00 Earth-like planets. And I can't say that we're really surprised, but so far, the little ones do not have atmospheres that we can tell. So, we shouldn't be too disappointed because we didn't really expect it, but we still do really want to know. So, what's next in this subject? Well, we need to build different telescopes.
24:20 Steph Smith? Tell me more about that.
24:21 Speaker 00 We are finishing up one now called the Nancy Grace Roman Space Telescope, and it will have an equipment to look for planets as direct images, a device called a coronagraph. So if we can get that to work, you never know, we might see some signs of more or less Earth-like planet. And the next one we're going to build is called Habitable Worlds Observatory. And so, when we do that, we'll be able to see an image with a little dot next to the other big dot, and it'll be an Earth-like object around a star like the Sun, which is a much more likely place to find signs of life. Because, of course, we've got one observation, which is us. Here we are. So, please look for another place like us. So we're building that, or I should say, we will be building that because that's
25:04 Speaker 00 what NASA wants to build, Congress wants to build it, National Academy of Sciences said to build it, astronomers want us to build it, and I think the public wants us to build this because, oh, I sure want to know, we all want to know, are we alone?
25:17 Steph Smith? We want to know. I mean, let me ask you a tangential question, which is just, there is this question, are we alone? Where did we come from? But then, there are also all of these questions that impact maybe our day to day, right, or us understanding what is happening on Earth. And so maybe you could just speak to that, how some of this cosmic exploration ultimately ladders back into what we understand about the things that we're building, engineering, science on the ground.
25:44 Speaker 00 Oh, a few things. One, general observation is that we NASA take on incredibly hard engineering challenges, like going to the moon with people.
25:52 Steph Smith? Yes.
25:52 Speaker 00 Or building this great telescope. And then we say, yeah, we actually can design, build, and cooperate to build something incredibly hard and difficult, and it can work. So it should give us reason for confidence and optimism that when we take on other challenges like managing our own little planet.
26:09 Steph Smith? Yeah.
26:09 Speaker 00 That we can do that. So we also, of course, at NASA, we take pictures of the planet. We watch Little Earth all the time. We have dozens and dozens of things looking down to map the circulation of the oceans, the clouds, and various atmospheric constituents like carbon dioxide. We see where it comes from. Methane, we see where it's being emitted from various sources on Earth. So we're providing the data that it takes to understand our little planet. Then some of the potential answers for how do we stabilize our planet and protect ourselves might have pieces of technology from space also. Some people are working on, well, can you generate electrical power and beam it down from space?
26:51 Speaker 00 Or can you block some sunlight with something in space? So there are lots of creative ideas. Some of them might work.
26:59 Steph Smith? Yeah.
26:59 Speaker 00 Most of them probably too hard or it won't work. But we can make up our minds sometime. Other thing that sort of generally observe is that we have exponential growth of problems and we exponential growth of capabilities. Like it used to be Moore's law about
27:14 Steph Smith? I was gonna say, semiconductors is kind of the
27:16 Speaker 00 So we knew that just got bigger and better faster all the time. And people don't really understand any of the details, but they just see that happens. And so we start off with, that can't be done. That's impossible. Then somebody invents something and then somebody wants some more. And gradually we invest our billions or trillions as it takes because there's a demand for it. And now we have a pocket computer that's far more powerful than we could have going to the moon with
27:42 Steph Smith? Yes.
27:42 Speaker 00 on the Apollo. So as an example, somebody heard this story. If you have a digital key fob in your car, it's more powerful than what we sent to the moon with the Apollo astronauts.
27:53 Steph Smith? Is it? Is that true?
27:54 Speaker 00 Yeah, honest. So that tells you the power of exponential growth. You just wait a long time and invest trillions of dollars and something will happen.
28:02 Steph Smith? Yeah.
28:02 Speaker 00 So when we say, can we solve the engineering problems of little planet Earth? Can we manage our climate? Can we manage our resources? Can we manage pollution? Well, yes, of course. The capabilities to manage also grow exponentially with time. And so when you say, oh, it can't be done. It just means we don't know how it can be done. But if it's important enough, we will do it. I've been to science fairs quite a few times to see what the young people are working on. And in the physics and engineering, there is a really large fraction of the kids are working on batteries, engineering, energy supplies, pollution control and resource management. So kids are already aware that's where the opportunity is. And our world is actually sponsoring the job.
28:46 Steph Smith? Yeah.
28:47 Speaker 00 Now, when I was only like 10 or 15 years ago, that people were very confidently telling us that electric everything was either it's impossible or too expensive, or it'll cost too much and we shouldn't do it. And now, anybody that wants can buy an electric car.
29:01 Steph Smith? Exactly. We actually just did a podcast on not just electric cars, but electric boats, electric planes, electric school buses.
29:07 Speaker 00 Every week I get another aerospace engineering story that says we have electric airplanes coming. Oh, okay. So, we don't know how to do it. It's not the same as we're not going to do it. And we don't know how to do it, doesn't mean we can't afford it. It just means we are lacking of imagination and patience.
29:26 Steph Smith? We've already touched on this idea that there's just still so many question marks about this universe around us. Is there a specific question mark that, you know, you would just love to see solved in your lifetime? Just even out of personal interest, there's something gnawing at you?
29:40 Speaker 00 I guess the ones that are obvious, that already are recognized by thousands of scientists, cosmic dark energy, cosmic dark matter, they seem to be there. We can describe them mathematically. They seem to fit practically everything that we know, and we did not expect them. There was no sort of basic understanding of anything that said they should be there. So, cosmic dark matter appears to be transparent. We shouldn't call it dark, we should call it transparent. There's a lot more of it than there is of ordinary matter, the protons, the neutrons, and atoms that you all see every day. So, it's out there. It has been detected by its gravity. So, back in the 1930s, we already had a hint that galaxies
30:24 Speaker 00 were spinning too fast, which means they're being held together by more gravity than you can find. You cannot find the stars to explain that amount of gravity. So, something is weird. So, it took from then until about 1980 something before we had a lot more evidence and we could say, yeah, this is really there. Do we know what it is? No. We have been hunting in laboratories for decades, and darn it, there isn't a single thing that's ever said this is a good promising candidate. So, that means it's a wide open mystery.
30:55 Steph Smith? Mm-hmm.
30:55 Speaker 00 Then we have the cosmic dark energy, which is something that, in principle, Einstein imagined. There's a place in his equations of the universe that could be called dark energy. But we thought, generally astronomers thought, that, well, that would never happen. So we imagined and believed that the universe's expansion will be slowing down because gravity is pulling on things and it will slow the expansion, which seems to be true up for the first roughly 10 billion years of the expanding universe, or 9 billion, and then it seems to be accelerating. So who asked for that? Well, it was discovered by people who were planning to measure the deceleration.
31:34 Steph Smith? Mm-hmm.
31:34 Speaker 00 And, oh, there's something wrong here. So they got a Nobel Prize for discovering the acceleration. It's going faster and faster every year, which means that if you were to come back in another, say, 100 billion years, most of the galaxies that we know about would have receded from us so far away that we couldn't see them anymore. So the universe will be in the process of appearing to empty itself out. And if you imagine going far enough into the future with just one Milky Way left, all the other galaxies are gone, the evidence of the history of the universe might have disappeared from science.
32:07 Steph Smith? Oh, that's fascinating. Just to confirm, though, you're saying it still exists, it would just be so far away that we can't detect it.
32:12 Speaker 00 Too far away to see it.
32:14 Steph Smith? Wow.
32:14 Speaker 00 So anyway, we are here at a particularly interesting time where we still have evidence and can write the story and tell ourselves how did we get here from something.
32:24 Steph Smith? What comes before the Big Bang? There is the Big Bang, and then you have all of this matter expanding, creating galaxies, et cetera, but like, it's hard for me to wrap my brain around this idea of what comes before it.
32:37 Speaker 00 Yeah, well, maybe that's because maybe there isn't anything before it. So the way I think about it is sort of from the observer's perspective, because what we see today is distant galaxies running away from us, and we see the cosmic microwave radiation that tells us what it was like when it was young. And we imagine running it backwards in our minds.
32:54 Steph Smith? Yes.
32:54 Speaker 00 So.
32:55 Steph Smith? Like a play button, literally, like.
32:56 Speaker 00 Run the play button backwards. So the galaxies go crushing together, the stars are ripped apart, the temperature goes up and up, eventually the atoms are ripped apart, even the protons and neutrons are ripped apart and separated into quarks. And then we picture this soup of quarks, leptons they're called. And then we say, well, what came before that? And so we have guessed that there's something called an inflation field, a purely conceptual quantum mechanical idea. And we say, if this could happen in this particular way, then it would produce the expanding universe that we have today. And so it seems to hold up in the sense that there are a few predictions that it makes that we verified by observation of the cosmic background radiation.
33:41 Speaker 00 So when this was first proposed, I thought, well, that'll never work. We'd never know. But there is a little bit of evidence that this cosmic inflation story could be correct. But it's still pretty much a guess. So then you say, well, what could come before that? And what does the theory predict? So the theory predicts maybe there could be other universes erupting out of this inflation field, and we would never know they were existing. There could be billions or trillions or an infinite number of other universes according to this idea, and we'd never know. But because this is so much of a guess, we honestly can't tell you what came before that.
34:17 Steph Smith? Yeah.
34:18 Speaker 00 And then we get to what about quantum gravity, which we touched on very briefly? If quantum mechanics should apply to space and time themselves, then what happens if time and space don't mean what they seem to mean anymore? And then kind of all bets are off. It means we are completely confused. We have no successful theoretical predictions based on that idea of quantum gravity. Doesn't mean there isn't any. But then it gets into all the wonderful questions about wormholes and quantum entanglement and the other mysteries of modern science and engineering.
34:53 Steph Smith? Oh, boy. My cosmic dust brain is.
34:55 Speaker 00 Yeah, well, my cosmic dust brain is not able to do that either. But somebody will be working on it, and some people are working on it, and we might get some breakthroughs.
35:04 Steph Smith? Do you think that there are any significant misconceptions about space? And that could be in terms of what we've discovered, but it also could be perhaps the way people view our investment into space?
35:18 Speaker 00 Well, I guess the number one misconception here that people have about space is that the Big Bang was a firecracker happening at a place in a pre-existing space and time.
35:28 Steph Smith? Okay.
35:29 Speaker 00 And so that's not about astronomy. We see the entire universe is expanding. It's probably infinite, so it's not a thing that happened at a place and time. It's the entire thing happening all at once.
35:39 Steph Smith? Okay.
35:40 Speaker 00 You know, because Sir Fred Hoyle gave it that name, we are instantly drawn to thinking of a firecracker, but that's not what it is.
35:46 Steph Smith? Okay.
35:47 Speaker 00 So there's that one. Then there's the other question was, what good is space research for mankind? And. There's lots of different kinds. One, of course, is that it's exciting for young people and we draw in new science and engineering people to study these things because it's exciting.
36:02 Steph Smith? It is.
36:02 Speaker 00 And then they go on to solve all the other problems of humanity. And some of it's also extremely practical. From space, we can see the Earth and study the Earth and see what we're doing to it. And we may actually do that part. Then, of course, NASA, among other things we do, is we have extreme demand for extreme objects of engineering. So when we need something, we'll invent it. And then it may have value elsewhere in our world.
36:29 Steph Smith? Yeah, and we've seen so many examples of this, right? Through, especially in the first space race, a lot of that technology was then applied.
36:35 Speaker 00 And a lot of it's not directly traceable, but because we're doing these things, it happens. So a lovely story from the Webb Telescope. The person who figured out how to measure the Webb Telescope mirrors while we were polishing them to get them exactly right, he went on to invent technology that you see in your eye doctor's office, so they can see the back of your eye much better. And even if you want, give you much better eyesight, you can get 20/10 eyesight from using this technology.
37:02 Steph Smith? Is this Lasik or are you talking about something else?
37:04 Speaker 00 It's Lasik combined with better measurements.
37:06 Steph Smith? Oh, incredible.
37:07 Speaker 00 So we use something called adaptive optics in astronomy. And so we learned some math and we've made some engineering and now it's in many doctors' offices.
37:16 Steph Smith? Yeah, well, I have to ask you, what do you think about this concept of us as humans, as little, you know, space dust creatures, becoming a multi-planetary species? And also, just, I mean, I'm uniquely curious to hear your perspective because there is a level of grounding in the science in terms of, you know, is it better to optimize what we have here on Earth? Or is it actually practical, worth being ambitious and trying to make that a reality on some of these other planets?
37:43 Speaker 00 Well, my perspective is we are a one-planet species. This is it.
37:47 Steph Smith? Okay, fascinating.
37:48 Speaker 00 Little planet Earth is a beautiful planet. It's nice and warm here. There's air and...
37:52 Steph Smith? It's a nice feature.
37:53 Speaker 00 None of the other things we can possibly reach are anything like it. The moon has no air. Mars is cold and has a little bit of air, but you can't breathe it. And you can't go outside without being bombarded with cosmic rays. And you're going to die in a few years if you do that too much. So just don't think that way. Earth is our home.
38:11 Steph Smith? Earth is our home.
38:12 Speaker 00 Take care of it. So there's a lot of wonderful imagination about going elsewhere, but there's no obvious path to do it.
38:20 Steph Smith? Maybe one other question that relates to our wider world is a phenomenon we're seeing is this lack of trust or a decrease in trust in institutions over time. Some of those institutions are scientific institutions. And so I'm just curious to hear your perspective on that, just your pulse, your reaction almost to that.
38:39 Speaker 00 Yeah, so one part of it is, it's not so much lack of trust is scientists have been discovering things that some people didn't want to know.
38:47 Steph Smith? Right.
38:47 Speaker 00 Because what we're doing is so important. It matters to people's lives daily. There's a pushback because they don't want to know this information sometimes. So it's been going on since Galileo, probably even before him. So the practical importance of what scientists and engineering are doing is immense. And so we don't always like the result. It's not so much that we're against science as that we don't like what's happening. So let's attack the messenger once in a while. But my reaction is it just proves how important the science really is, that it matters so much that people are fighting about it.
39:20 Steph Smith? Yeah. And if it's so important, how do you see the involvement of private versus public dollars going to that? Or how would you think about that?
39:28 Speaker 00 Well, the public dollars come because our representatives have decided it's important for the whole country to do it.
39:34 Steph Smith? Yes.
39:34 Speaker 00 So sometimes it's for actual personal daily benefits like health. Sometimes it's for prestige matters. The United States should be showing the world that we're great leaders in the cause of freedom and science and democracy and so forth. So the Apollo program was an example of that. Don't mess with us. We can do anything we like. And it sort of worked. The Soviet Union did not attack us. So there are a lot of different versions of why the public dollars are spent. But I would say, having been to visit the committee room for the House Committee on Science and Technology, it's covered with space pictures. They love what we do at NASA and it's visible. The public can see what we do. You can't make a pretty picture about a virus.
40:18 Speaker 00 But the viruses are actually even more important.
40:21 Steph Smith? Mm hmm. Well, for us on Earth. All right. Well, let's close out on one more question, which is, you know, you have been working in this industry for a very long time. And we'll see where longevity science goes. But if you did have hypothetically 100 more years to work on something, is there some big ambitious project that you would love to, you know, get your hands on? Is there something that you would really love to be a part of yourself?
40:45 Speaker 00 Well, I have some ideas of things that I'm working on now.
40:48 Steph Smith? Yes.
40:48 Speaker 00 But they're probably not going to last 100 years.
40:50 Steph Smith? Mm hmm.
40:51 Speaker 00 The things that do look exciting 100 years from now, it could still be the dark matter and the dark energy and the search for life elsewhere.
40:57 Steph Smith? Yeah.
40:57 Speaker 00 In my sort of territories.
40:59 Steph Smith? Yeah.
40:59 Speaker 00 Here on Earth, I think we're going to see astonishing growth in artificial intelligence. And it'll be a powerful tool and a powerful weapon. And we'll have to get used to it because it's going to happen very quickly. And it's not so long ago that really smart people were telling us it could never happen. And now
41:16 Steph Smith? And here we are.
41:17 Speaker 00 Really smart people are telling us, oh, my God, I'm scared to death.
41:20 Steph Smith? Well, you said yesterday, another great quote was basically, while we're busy worrying, technology advances.
41:26 Speaker 00 Yeah, it really does. And if you want to know what's happening, see where the money is going. Many, many billions of dollars are being spent on artificial intelligence. And so if it's possible, it's going to happen.
41:38 Steph Smith? Yeah. Well, John, this has been an absolute joy. Thank you for your contributions to this world. And thank you also for, I think, something that really resonated throughout this conversation is just this level of optimism that this human species, even though there's so much we don't know, it's worth us trying.
41:54 Speaker 00 Oh, yeah. I'm thrilled to be here with you. And yes, I really have an optimistic viewpoint, which is drawn from, I think, reality. We see terrible news in the news all the time, but that's because that's the only kind they print. Good things are happening, and we can find them if we look.
42:10 Steph Smith? I love that. Well, thank you so much, John. This was amazing.
42:14 Speaker 00 And thank you, Steph, for inviting me to join you.
42:21 Steph Smith? Thank you so much for listening to the A16Z Podcast. If you liked this episode, if you made it this far, help us grow the show. Share with a friend, or if you're feeling really ambitious, you can leave us a review at ratethispodcast.com/a16z. You know, candidly, producing a podcast can sometimes feel like you're just talking into a void. And so if you did like this episode, if you liked any of our episodes, please let us know. We'll see you next time.
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