From Big Bang to James Webb: Exploring Space with Nobel Laureate John Mather

0:00Right 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 Earth's 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 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.

0:40Artificial limbs, precision GPS, fire fighter suits, insulin pumps, emergency plane kids, air purifiers, even the dustbusters. 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 we think they know what is best to build. Without realizing that there are so many great things that have sprouted from projects that didn't seem immediately useful at the time.

1:28And 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 Kobe Satellite, to which, by the way, Stephen Hawking described the imagery from Kobe and its implications on the Big Bang Theory as the most important discovery of the century. if not all time. 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.

2:13Now this episode came about because I had the pleasure of seeing John speak at the Aspen Ideas Festival and after his talk I 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 in this space, but also the many things that we have yet to understand. So things like dark energy and dark matter. Plus, we explored the very important question of why space exploration is such a fundamental, but also useful human desire in the first place.

2:57And given that the James Webb Space Telescope that John has been working on recently made its first detection of a new carbon compound, methyl -cat ion, 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. 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.

3:36Please 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 a16c .com slash Disclosures.

3:52Maybe 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? Oh my goodness while 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 rockets were possible. So then we signed it, got busy. And we discovered the most astonishing things.

4:31We 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 in 1957, so yet Union launched a little sputnik. Suddenly the government realized we better invest in science and engineering. Yes. They played 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.

5:11And 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. A lot of them. Because some things are harder even than space engineering. Tell us about when you started getting involved in this. Oh my God, it's drastic. Pretty young. I think I was about six years old. Wow. I heard from my dad at bedtime story time that living things are made out of cells with chromosomes.

5:47And this was before we even knew about the double helix. So, that's right. That got my attention. My friends and neighbors were farmers. My dad was studying dairy cows. Wow. For his research, for a rectalous university. And so that was where I got started. Yeah. 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 it was about eight. We went to the museum of natural history in New York and the Planetarium show and the giant meteorite sitting there.

6:23It's big as a small apartment. Just sitting there and say, where does that come from? Where do we come from? Where do we come from? So you see the bones arranged in showing evolutionary order in the museum? Oh my god, what a fascinating story. I want to know everything about this. 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 want 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 and what that really meant as maybe an inflection point.

7:03So 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. It is thought to be the remnant of the early universe, the hot big bang, so it 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've 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.

7:40And 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, okay, well you did good work, You can write this up, you can make a thesis out of it. They've already published some other papers. So I said, okay, 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. Wow, okay. So, okay, 1974, I met NASA Laboratory in New York City. And, okay, so NASA puts out this announcement of opportunity, calling for new satellite missions for science. Because what are we gonna do after the moon landings are done, maybe do something else?

8:20because we can't keep on going to the moon all the time. So, okay boss, my thesis project failed. We should try it in outer space. So, I had no idea how much nerve wasn't required to do this, but 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, and it worked. And within weeks we had measured the spectrum.

8:57The Mythesis project that had failed as a blue payload, now worked beautifully in outer space. That's incredible. I showed a graph to the Astronomy Society, and we got a standing ovation for a graph. And so they knew how to mint. 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.

9:33And what they show is, if you could see a millimeter waves with your eyes, you would see this big fuzzy map. And 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 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. That is. It used to be people looked at this amazing universe and thought It requires divine intervention because it's too dang complicated.

10:13Nobody could possibly see how it could work. We confuse, I don't know how it works, or I don't know how to do it, 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. We divert into that a little bit, because how is it that nature spontaneously produces complicated stuff? Yeah. So there are reasons. There are fundamental deep reasons why nature produces complicated stuff. 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.

11:01But 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 it into about thermodynamics, which tells us which kinds of reactions are favored by nature. So, if energy is released when two atoms come together, then it's likely to happen. 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.

11:39Yeah. 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. Okay. 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 into 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, some places, and cold other places.

12:18So energy flows from place to place. And this is then the basis of the complexity that we now have. 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? 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. Yeah. All the same temperature, completely boring as far as workings or we wouldn't be here.

12:54We wouldn't be here. 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. Oh, that's not really the right word. It is a universe in which complexity naturally appears. 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?

13:33Okay, 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. There you go. There you go. 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 know it exists. Yeah 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.

14:17Scientists have been working at least 50, maybe a hundred years, trying to figure out how gratifity 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 are 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. Yes. And so it's totally fascinating and draws in thousands and thousands of scientists.

14:52Since the Kobe 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. Let's talk about that, right? So you were the lead project scientist. We're senior project scientists 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.

15:28After the Hubble Telescope was launched, scientists said how wonderful it was. 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 saw, 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, all we get 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.

16:06So you've got your own time machine in your eyeballs every morning, but you don't feel it. So, look back in time, see what the universe like when it was young, and see what the galaxy is 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 web telescope. It did what it was supposed to do. It produced beautiful pictures, and right away we could see that the galaxy 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.

16:47So we're looking for something really deep and fundamental. Don't know what it is. 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 and 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 than we can't even imagine it yet. Why don't we actually look at some of these images from James Webb? Oh, okay. So we have something that Joe Biden released at the White House on July 11th last year.

17:22And 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, 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.

17:58And 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 various 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.

18:42We 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, so 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. Yes. And so we know they're there because we see things orbiting around them, so we calculate that there's something inimously massive object in the middle.

19:23Sometimes 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, while 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. This is with the James Webb or? That was done with a LIGO observatory, which is here on the ground.

19:54And 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 redding ring of gold, then we know that most of the gold in that redding ring came from neutron stars that collided and blew up and the material came back out into spaces 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 in blue up. And so our own personal story is got the most remarkable threads in it.

20:32I 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. Yeah, sure. So yeah, everybody wants to know, are we alone? Yes. 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 a rather elementary.

21:11And 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 on planet Earth but it's not very likely to be space aliens. Yeah.

21:45Something 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. 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.

22:26And so for lucky we might find out there are organic molecules in those oceans. I would say maybe there's life under there. And so it'd give 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 Earth's 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 other smaller stars that are called M stars. So these are very weak little stars. Our hardly as big as Jupiter.

23:04How about they're warm enough to - Hardly as big as Jupiter. It's just funny with our sizes. Yeah. Well, just 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. It's good for you. Good reference. 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 it will go in front of the star, it will block some starlight. So, okay, now we know it's there. We can calculate its temperature and its size, and whether it possibly host an ocean.

23:38Okay, 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 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.

24:14But we still do really want to know. So what's next in this subject? Well we need to build different telescopes. Tell me more about that. 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 Hepatable World 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.

24:55Because of course we've got one observation, which is us. Yeah, 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 what NASA wants to build. The 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 I don't want to know. I don't want to know. Are we alone? We want to know. 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?