Onepod Podcasts

Subu

Hello folks! Welcome to another episode of the half-life show. We have something really special for you today. Recently we saw the deepest images of the universe from the James Webb Space telescope, and Astronomy has been a childhood dream in so many of us. But some people go on to make that dream a reality. In this episode, we have on the show, Dr. Harish Vedantham, a professor of radio astronomy at the University of Groningen in Netherlands, his research specializes in exoplanets or more simply put planets in other solar systems than our own. Join us on our journey with Dr. Vedantham, as he discusses some of the most fascinating problems in radio astronomy, his dream of building a radio telescope on the moon, the astronomer's lifestyle, alien life and how the meaning of life is from within and outside the realm of science. Now onto the episode. Okay. Harish. Welcome to the half-life show. Glad to have you here.

Harish

Well, thanks a lot. I'm very happy and excited to be on your show. I've been listening to all the episodes and you guys are on your way to be the Joe Rogan of the desi experience,

Vikram

I'm not sure whether to take that as a compliment or not.

Harish

For something that's not a compliment.

Subu

So, Vikram I'm, I'm happy to hear that we have at least one other listener apart from you and I.

Vikram

Done. We are adding them One at a time, The more guests we add, the more we are sure we'll have at least one listener on that episode.

Subu

That's right. All three of us essentially had very similar upbringings, right? I mean, we went to similar type of schools. You and Vikram were classmates all through undergrad, and then we all came to US to do our master's at the same time. But at some point our paths diverted completely, and you're doing something, which I don't know if I would have ever guessed this is where you would end up. So maybe you should start by telling us what you're doing now. What do you, what you do for a living. And then at some point later we will get into how you got there. But yeah. What do you do.

Harish

Yeah, sure. I must preface my answer by saying that you guys went to fancier schools than I did. And, you are way cooler than me in college because of the music. but yeah, I agree with you. We had a kind of typical middle-class Indian upbringing. Anyway, so what I do right now is I'm an astronomer. I work at the Dutch Institute for radio astronomy in the Netherlands, I also have an appointment as a assistant professor at the university of Groningen, and essentially, my life. My work life is, full of research in astronomy and astrophysics, whatever you want to call it, teaching, advising students that kind of stuff.

Vikram

So at some point, like what Subbu I had, when we was preparing for all these entrance exams, and when we got into engineering colleges and we all studied together, especially you and I were project mates. And we did like similar stuff. Like electromagnetics was our main focus, right at the time. And even in grad school, when we came to the US we did a lot of electromagnetics. So that's the direction we went to. But then after both our PhDs in somewhat similar topics, like your work went completely academic. And at some point you actually were a fellow at Caltech, right. Doing radio astronomy now. Subbu correct me if I'm wrong, but don't you think that as like kids or, teenagers we actually dreamed of what it would be like to work at the same Institute like Richard Feynman, did, working on physics and that's what our friend here, has done. I find that pretty amazing actually.

Subu

Yeah. Yeah. The minute you tell me, someone did research or studied at Caltech the next time I see them there's an aura or a glow around their head. And right now I'm looking and HVK and that's exactly how it is. It's as if HVK was just a friend, but

Harish

Maybe I've been smoking some good stuff in California, but yeah, from what Vikram said, it's true that we kind of diverged maybe at the masters or towards the end of our masters in the United States. , maybe we'll get to the timeline, later, but, I can say that there was always a streak of, kind of a being an academic in me. It just that I didn't realize it until much later. I mean, you could say that I wasn't mentored, in the right way during high school. So I couldn't realize that early on in my life, but turned out that, it all worked out fine actually. We all got a good education and there was a solid base to move into a slightly different field and it all worked out.

Subu

Yeah. Actually coming to think of it. Right. HVK was always very good at explaining stuff. Even if he's explaining the most useless of things, I mean, we were sitting over a bunch of whiskeys and he's just randomly and we are all, randomly chatting about some stuff somehow HVK is the one who always made most sense. You are a professor, right? So you do spend a lot of time teaching and not just research.

Harish

I do teach. Yeah, definitely. It's not just research it's research and teaching and also mentoring. So I have PhD students. So I also mentor students.

Vikram

so he has a natural flair for teaching right here. He used to teach us a lot of, stuff in college and that maybe it was a latent skill you had, which you are realizing to the fullest potential. Now.

Harish

that, that, I think that's absolutely right when I was a PhD student, student PhD students also, help with teaching. But they don't take the full responsibility for a course. So when I was a PhD student, I taught a little bit and that's when I realized that I really enjoy this. I used to put a lot of time, , into preparing for teaching and I used to actually really enjoy doing that. And now that I teach, a full course, I take the full responsibility for the course. Yeah, I'm absolutely enjoying it. Teaching is very rewarding. The look you get on a student's faces when they really understand something that they have some kind of an aha moment is, is very rewarding. I enjoyed it immensely. . Subu Ganesh: Yeah. Yeah. Actually, when you say students, it doesn't necessarily apply to only young adults and teenagers, right? Maybe about five or six years ago. I was like, what? 33? And I took this class , a programming class and it was a week long programming class. And I had no one had ever taught me programming in such a profound way as this teacher. I, I this class I went to and a lot of things changed when I turned 33. After this one course I can attribute I I've become a much better engineer and I have developed a lot of interests and I kind of feel like my life in general has been a lot more interesting. And if I were to trace back in the timeline, I would put the pin on this specific week, long class that I took when I was 33. So teachers can really make a life-changing

Yeah, absolutely. I mean, a lot of people will have a story like that. They met the right person at the right time. Maybe, it's, it's, it's sometimes a teacher that sometimes just a mentor. And so when, when I'm teaching, I'm trying to be mindful of the fact that I'm also a mentor at some point. Right. And so it's not just teaching the subject material. But it's also conveying a sense of excitement for the subject excitement, just for academic life in general or the, the excitement you get for figuring something out trying to motivate them to, be a little more independent, think for themselves, if it's a hard problem, that's fine. Give it a shot. You'll probably fail the first time. That's fine. Everyone fails the first time. So that kind of all the soft things around, the, the hard stuff of, of the material itself, what you're teaching, that's super important. And we all have a storyline that where, we met a right person at the right time. And of course now, now that I'm on the other side, the trick for me is to try to be that for as many people as possible.

Vikram

Speaking of hard problems, right? Your scientific research is probably among the hardest things I can imagine. So why don't we speak about that? The exciting world of research that you do specifically, radio astronomy and all the little details of, what you're looking at.

Harish

Sure. Yeah. I've worked in a bunch of different fields in astronomy. I mean, what I'm doing right now is completely different from what I did for my PhD. For my PhD. I was basically looking at reducing data from, from a new telescope that was just built in the Netherlands. It was a radio telescope and we were trying to detect this really faint signal that comes from the very early universe from a time when the first stars and galaxies were formed. I mean, we are still trying to detect it. I mean, these are really long, hard questions, which well hard questions, which take a long time to solve. But that's how I cut my teeth. So to say during my PhD, but what I'm doing right now is it's completely different. So in the last three or four years, I have really gotten excited by what's happening in the world of exoplanets. And I'm a radio astronomer by training. So, what I basically do is use radio astronomy to see what we can learn about exoplanets. So we have, I've started a big program now to observe radio emissions from nearby stars, exoplanets brown dwarfs, which are these really interesting objects that are too small to be a start. So they're too small to have sufficient pressure in the interior to burn hydrogen like stars do, but they can burn an isotope of hydrogen called deuterium. So it's they can do that for a short period in their life. And then after that, when they run out of that fuel, they're basically like a giant ball of gas, like Jupiter, and they just cool. so the, these are the objects which are in between stars and planets in terms of mass

Vikram

Quick question. How do you define an exoplanet for those who haven't heard the term?

Harish

Oh yes. An exoplanet is a planet that is going around the star other than the sun. That's a most basic definition. So our sun is a star. It's pretty average that there are lots of stats. And from what we know right now, I mean, almost all stars have a planet, a system around them. So all of those planets are called exoplanets. It's a short form of extra solar planet.

Subu

Okay. So a couple of more simple questions. Now, the, the exoplanets that you're observing, right? I mean, when you look at the sky, the whole space is so huge. Are you focusing on one specific area of, space or, when you're studying exoplanets and so on? Should we just assume that, Hey, you're scanning the whole night sky or just to put us in the right perspective.

Harish

Sure. I mean, there are a few observational strategies, which, all astronomers use. One is what you would call a targeted observation. Like, so you would say, well, I know where all the nearby stars. And the exoplanets are just going to be around those stats. So I'm going to point my telescope to this star here and then this star here and this star here and keep going and try to see if I can detect something like, and that's kind of a targeted strategy. You can get a little more complex there you can say, I'm going to target this kind of star, a star of this particular age or this particular temperature. So you select to maximize your chances of discovering something. There's something which astronomers also do, which is called a survey. So, what you do is you just say, I'm just going to survey the whole sky and see what, what there is, right? And so this night, I'm going to point at this patch of sky I'm going to expose for a long time. And then the next night I pointed the next patch of sky. And so you kind of keep piling and covering the entire sky, but of course you have a finite amount of time. So when you do a survey, you can't spend too much time on one particular part of the sky. So you get a shallow exposure of the whole sky, like, so you've got a wide angle image in the end, cause you cover the whole sky, but it is shallow. Or you can go a small part of the sky where you have a few targets of interests, but go deeper. You expose the longer. Yeah.

Vikram

What kind of exposure times are we looking at to get something that's a deeper look into the universe.

Harish

So. Well, it really depends on what you're after. And what usually ends up happening in astronomy is all the bright stuff's already studied, right. In the sense that radio astronomy is started after the second world war I, to a large part, it actually started with all the equipment leftover from the war. These were the radars. And so people just forgot about the transmitter and use just the receiving part of the data. And in some sense, that's how a lot of radio astronomy got started. And so of course, the first thing you're going to find when you start a new field like radio astronomy, before that astronomy was mostly optical. So people were looking at light in the optical domain. So this would be the light, which your eyes can see radio waves at the same kind of radiation, just like light. But there are very, very low frequency that your eyes can't see. So you need antennas to catch those waves. So anyway, when radio was formally started, of course, all the brightest sources were the first things to be found because the equipment then was not very sensitive. Right? And so as you go to more and more sensitive equipment as technology improves you're going to find fainter and fainter sources. And of course your ambition goes up because now. Things, which you couldn't have seen before, because you just weren't sensitive enough. So what kind of exposure do you use really depends to, just to give you an idea, the project on which I did my PhD, that's thousands of hours of exposure on a single field in the sky. So think as one part of the sky chosen and thousands of hours of exposure, trying to detect a really, really faint signal. But there are other cases where you don't need that kind of exposure. So radio astronomy also has signals, which are coming from sources that are very fleeting. So there's a new phenomenon called fast radio bursts which was only recently discovered where people found a millisecond duration flash of radio waves coming from outer space. Right? And so there, there's no question of exposure. The signal only lasts a millisecond, right? So you just need a big enough telescope says that in that millisecond, you catch enough energy from the source so you can detect it.

Subu

Do we know what it is? Do we know any hypothesis or theories on what it could be or where it's coming from?

Harish

oh, there are a lot of theories. There was a time when there were more theories than bursts detected for the whole cottage industry of people, imagining every kind of cataclysmic event that can happen in the universe. We still don't know for sure. People have narrowed things down. But no, we don't, we don't know really, for sure. Right. It's a real mystery because these flashes, they just last a millisecond. Right. And so, uh, one of the really nice things in astronomy is, you can work out a lot based on just causality, causality, being that the cost should come before the effect, right? So if something lasts just a millisecond, then you can argue that the source cannot be too big because if the source is too big, then how do all the charges or this huge amount of space know that they need to emit light. Now in this one, millisecond, they can't, they can't talk to each other faster than the speed of light. Like they can't know about what the other sources doing faster than the speed of light. So you multiply the speed of light by a millisecond. You get a distance and the source has to be smaller than that. And so you come to a really tiny source and these signals are coming from, cosmological distances, so billions of light years. And so how can so much of energy be packed into such a tiny part of space? So it's a real mystery.

Vikram

The field of radio astronomy , has so many such interesting stories and mysteries and things like that. I do remember one such story is how these bunch of radio astronomers were, trying to find out the source the origin of the universe and the big bang was still a theory and all that.

Harish

I think you're talking about Penzias and Wilson's discovery of the cosmic background

Vikram

it. That's a good story.

Harish

technically they were not astronomers. They were actually engineers.

Vikram

Okay. There you go.

Harish

They were actually engineers. So they're for communication purposes, I think. So they were proper engineers. These, these are very early days of radio astronomy. I mean, in the very early days of a field people are a little more technical in the sense it's both an astronomer and an engineer because nobody really knows how to build these things. So you have to be a engineer or, some people might call it applied physics. You have to be somebody who knows how to build the instruments anyway, coming back to the story. So they were really trying to perfect this instrument. This was just a big antenna receiving radiation, and they were trying to work out how much noise there is in the receiver. So noise is just an unwanted signal. It's all always there. Even if you build a perfect, receiver you can you're always gonna have some unwanted static in that we see whether it's this hissing kind of static, which is just that because of thermal motions of charges. Right. And so they were trying to work, work out how much noise there should have been in the receiver. And they always got an excess and they never quite could figure out why is there this excess noise? And it worked out to be about in terms of temperature. It, it worked out to be about three Kelvin of noise. Okay. So, 300 Kelvin is roughly room temperature. So it was about 1% of room temperature. So imagine you're trying to measure the temperature and you're expecting 300, where do you get 303? That's kind of a rough analogy. And they can't work out where these three Kelvin comes from. And so they met up a bunch of I don't know, physicists, astronomers I think at Princeton I might be wrong and explain to them what was going on. And and by that time it was obvious to the people that the astronomers that these people are actually made such a monumental discovery without realizing that they had made a discovery. And so that was the leftover after glow of the big bang.

Subu

wow.

Vikram

And the funny thing is when they found this, three degree difference from the background radiation, that they, what they expected to find in the middle. They actually thought it was because of all this pigeon poop that was on the antenna. So they actually went and took a rag and they, they wiped all the poop. The three degrees didn't go away still.

Harish

no, these guys pulled all the stops. I mean, they, they really tried to hammer down and figure out where the, where it is, this excess of three degrees. Like we must have done something wrong and they couldn't make it go away. It's kind of similar to what happens even to us, I mean, just normal astronomers like me because we have, because most of it happens in basic research in general, because you are doing things which haven't been done before. So there's no blueprint for how it should be done. There's no clear expectation of what you should see. Absolutely. See. And that was kind of a shift in mindset going from engineering. What I studied to, to doing this kind of blue sky fundamental research, but you, you don't really know what's going to happen on what you are exactly. Supposed to see. You have some basic ideas. And so even if there is a discovery that is staring at you in the face, from the computer and monitor your first thought is, and for a good scientist, I'll argue should always be, I've made a mistake. There must be something wrong like this, this is too fantastic to be true. And in most cases it is too fantastic to be true. It is something stupid. But you know, you have to be perseverant and lucky to chance upon the three Kelvin, which Finzis and Wilson.

Subu

Nice. That's excellent. So now with your experiments, all of the stuff that you've been doing with exoplanets what do you, I mean, what is the aim? Why are you doing this? What, what do you hope to observe?

Harish

Sure. Yeah. So I think the best way to explain this is to think of our own solar system. Okay. Because we are trying to replicate what we, we know in the solar system to other worlds, right? Where these extra solar planets, I don't know the stats. So you can look at the solar system and ask like, what good are radio waves in terms of studying what's happening in the solar system. And it turns out radio waves are fantastic for, for basically figuring out what's happening in with plasmas and magnetic fields. Okay. So plasma is just a state of matter where if you take a hydrogen atom, it has a proton and an electron. And if they're bound together, it's hydrogen gas. But if you knock the electron out, then you just have protons and electrons. Separated from each other and that is plasma. Okay. And so it turns out that with, with radio waves, you can study what's happening with plasma and plasma is very important. So I can give you an example. The sun has a Corona, which you can see during a total solar eclipse, like many of your listeners have probably seen one that white wispy thing you see around the sun is the Corona. Now that gas is at a million degrees Kelvin. Okay. So that is very hot plasma and it's constantly expanding. So there is a wind of plasma that's constantly blowing from the sun and all of the planets are bed in that wind. Okay. And every now and then there's a huge explosion on the sun. I mean, you don't notice it just walking around, but there are these explosions that happen on the sun. We call them flares. And in some of those flares, there's a huge amount of plasma that is ejected into the interplanetary medium. Sometimes it comes towards the earth. You might have heard of predictions of Northern lights in two days or whatever. Right. And so that prediction is coming from the expectation that this huge blob of plasma is going to hit the earth. Okay. And that kind of plasma is actually harmful to the atmosphere of a planet. What can end up happening is the atmosphere just get eroded from this plasma. So this plasma it's like, think of it like a stream, okay. Like a river stream and you put anything in a river stream, it's going to start trying to drag everything with it. Right. And so it can drag out the atmosphere of planets with this plasma. And so figuring out when you have this huge plasma ejection events is important. If you want to know if there can be life on a planet around another star, right? Because that'll tell you something about what the atmosphere of this planet is being subjected to, and this is happening for billions of years. Right? It turns out that there is a very clear signature that appears as radio waves when this plasma is injected. And we see that on the sun routinely. It just, that we've never been able to see the same on a star other than the sun, because these stars are so far away that, you really need sensitive detectors or telescopes to, to be able to detect that signal when it happens on the sun, it's exceptionally bright. It that's just because the sun is very close to us compared to the other stuff. So part of my research is trying to look for similar, radio signals from stats other than the sun. So we can say something about what is happening to exoplanets. Okay. So that's the sun end of the business. On the planet side, you would have noticed that we haven't lost our atmosphere and we haven't lost that atmosphere because we have a magnetic field. So the earth has a magnetic field. That is why a mariner's compass works. It can point to magnetic north just because the earth is a giant magnet. Okay. So the magnetic field of the earth is about one gauss. That's weaker by a factor of 10 or a hundred, then you'll have that fridge magnet. Okay. So it's weak, but it's huge. It's on the scale of the earth, right? Near fridge, magnet is tiny. So anyhow, this magnetic field is what is protecting the earth from all of the plasma. And so it actually ends up channeling that plasma into the polar regions. That's where you get the the Northern lights and the Southern lights at high latitudes because all of their plasma goes towards the poles. Now Mars doesn't have a magnetic field and it's lost half of its atmosphere already. And one big reason possibly is because it just doesn't have the magnetic shield that the Earth has. So then the on the planet side, you want to be able to detect the magnetic field of a planet. And it turns out that the only way we know of how we could do that remotely without actually going to the planet with a magnetometer is by looking at radio emissions from the planet. And we have done that for solar system planets we've measured the magnetic field of Jupiter, even before spacecrafts were sent. Because we could detect radio waves coming from Jupiter and using that you could measure the magnetic field of Jupiter. And so the trick is now to do this on exoplanets. And again, because they're so far away compared to Jupiter or the solar system planets you just need a massive telescope. So it has the sensitivity to see this. So, the other part of my research is to look for these kinds of signals from exoplanets.

Vikram

And so if you do look for the signals from such exoplanets and you do detect it as a magnetic field, then you can tell that basically that magnetic field is protecting the planet's atmosphere from the solar flares of its star or its sun. And therefore the protected atmosphere has a high chance that you might now, find life on such a planet. Is that the thought process,

Harish

Yeah. I mean, I'm simplifying things here. I mean, reality is always a little more complicated, but at a simplified level, that's true. So life as we know it, which is to say life on Earth is going to be helped immensely by the planet having this, magnetic field. So it just, it's a necessary, but not sufficient condition for life has been. Yeah. So it's one piece of the puzzle. That's, that's how I would say it. It doesn't think of the question of, is there life or can there be life on other planets outside the solar system? Think of it as like a huge puzzle. And one piece of it is, does the planet have a magnetic field? And another piece is how friendly is the star? I mean, how often that this huge ejections of plasma happening on the stuff.

Vikram

Awesome.

Subu

Following up on Vikram's question right now, even before we get to figuring out if a planet, if an exoplanet has a magnetic field or if it is capable of having life on it. I read somewhere that, even finding an exoplanet is quite is quite a difficult task. Like, you first observed a distant sun and then you see if it has shadows passing in front of it, and then you develop some theory that, oh, that could be a planet going on. So now before we analyze an exoplanet, how difficult is it to find? How many is it? Do we find exoplanets every day? Or is it something that happens once a year or like, I don't have a feeling for how often we find these things.

Harish

Oh, right. So to give you a numbers, we have I mean the field of exoplanets is just exploded. Right. So right now finding exoplanets is more or less routine. I mean, it's still challenging, but it's not. Yeah, you need to slog for years to find one exoplanet. So to give you some numbers, we have now discovered about somewhere in the vicinity of 3000 exoplanets. Okay. So finding an exoplanet has sort of become routine, but of course the challenge is in, is in finding smaller planets because they're just harder to find the huge, the Jupiter, like exoplanets are easier. And also it's. So now, so now really the focus is shifting on not just doing the census of exoplanets, which is to say how many exoplanets are there and what type of exoplanets that's all going on. But a lot of focus is now shifting on characterizing those exoplanets and trying to figure out, do they have an atmosphere? What species are there? What gas species are there in the atmosphere? The atmosphere look similar to the Earth's atmosphere that kind of stuff. So when it comes to the radio observations the telescopes we are using right now, they don't have the angular resolution to separate the stars from its exoplanets. So the star, the exoplanet, the interstellar system is in one pixel on the sky for us. Okay. So that's all we get. We get one pixel, we get brightness radio wave brightness as a function of time, frequency, polarization from one pixel on the sky. And you need to tease out where the emission is coming from. And so you use your knowledge of the kind of emission, the properties of the emission that can come from an exoplanet. Vis-a-vis the properties of the emission that could come from a star from the corona of a star. You use that knowledge you have already, which was actually built up, not just by theory, but also by observing the sun and the other planets in the solar system. You use that to piece out the two different signals. So you can say, okay, this signal with these kinds of properties, that must be a planet in this system. So there might be instances where we might detect a signal from a nearby, from the direction of a nearby star, and it really has the smoking gun signature of it coming from a planet and not a star. And so it could be that that planet has not yet been discovered. So then we would go by other means and try to find this planet.

Vikram

Maybe you are the perfect person to ask this question to because you actually work in this field of discovering, exoplanets and, analyzing them and all that stuff. Last year, we launched the, the James Webb space telescope, which was under construction for like a couple of decades, cost probably 10 billion. And it's the successor to the Hubble space telescope, which gave us some amazing images of the universe that we never saw before. So maybe you can explain to us what, what is amazing or spectacular about the James Webb telescope

Harish

yeah. So James Webb space telescope, I mean, in a very simple, way, I mean, Hubble is the technology from, decades back. Right. And so a lot of progress in terms of just the detector technology. So James Webb will just have better detectors, more sensitive detectors. It's a much bigger mirror then Hubble has. And basically if you have a big enough mirror, you're just collecting more light, right. That's coming from a distance source. So when you collect more light, you're able to see fainter and fainter sources. And so th that's the other advantage. James Webb is also designed to do a bunch of things which are, are more how do you say that they're designed to do things which are immediate scientific opportunities. So, even the science we do or, or the topics we study, change over the decades we just like in any other field,

Vikram

we have

Harish

Topics, which are really hard in the sense that there are a lot of interesting discoveries coming in that in that sub field of astronomy. And we also have cases where some cell sub-fields become a little dormant because, with the current technology, we just can't go further. Right. And so that they kind of go out of fashion, so to say and come back in fashion. So everyone's really excited about James Webb because it's really perfectly designed to do a vast range of things which are kind of like burning questions in astronomy, right now. And we are just at the stage where we have the technology to be able to answer those questions in terms of, the telescope and it's detectors.

Vikram

What are some of these questions that James Webb telescope can now answer with the technology it has built in

Harish

Yeah. So one of, one of the things which it's a huge range, I mean, any flagship mission like this, that's going to cost like 9 billion of whatever that number is. Of course it's going to have a very broad tent. So, they're going to be a lot of different astronomers who are going to be using James Webb. I, the one, the things I'm most excited about with James Webb is it's an extremely sensitive in the infrared part of the spectrum. Okay. So infrared. Just like light, but the wavelength is longer than optical light and we can't see that with our eyes. But the nice thing about infrared is that most of the starlight that comes out comes out in the optical light. And that's why we have eyes that can see in the optical because most of the sunlight comes out in the optical. So we have evolved to see that part of the spectrum where most of the energy or most of the light comes out from the sun. Right. But if you want to look at stars, which are way, way further out in the universe, looking further out is like looking back in time, like, because light takes time to travel from there to here. So when you're looking at the sun, you're looking at how it was eight minutes ago. Actually when you're looking at the moon, you're looking how it was two seconds ago and so on, right. I can go up until the edge of the universe where light has taken billions of years to get here. But what also ends up happening is all of the light that was emitted in the optical by those stars, the first star, which was born in the universe, they are all getting shifted to longer and longer wavelets. So what was emitted in the optical will eventually shift to infrared by the time it comes to us. And so James Webb is fantastically sensitive in the infrared. So one of the things which is very exciting for me at least, is we'll be able to see these first stars and galaxies, which were born in the universe. And I guess I'm partial to that because my PhD was on, on that topic. I'm also excited about what James Webb can do for exoplanets. Again, just because it is just so fantastical sensitive. And there's a lot of excitement around trying to measure trying to do what is called a spectroscopy. So in this case, you're taking the light and you're breaking it up, breaking it up into different. Wavelets just like what Newton did with the prism. Like you pass light white light through a prism, you get the constituent colors right. And so when you do the same two light coming from a Starlight, which is filtered through the atmosphere of an exoplanet, for the sake of argument you break that light into different wavelengths and then you start seeing the fingerprints of different chemical elements in that spectrum as we call it and having a fantastically sensitive instrument is necessary to do this because as you can imagine the planet just blocks a tiny amount of Starlight, and it has a thin veneer of an atmosphere. So of all this Starlight that's coming, it's a tiny amount of light that passes through the atmosphere. So you need really sensitive spectrum to be able to figure out those fingerprints. So even though I'm a radio astronomer and I don't directly use James Webb data I mean, it's just going to propel the field forward. And as is typical nowadays, I mean, the, the thing of, okay, I'm a radio astronomer. It doesn't mean that I don't do optical observations. Although my expertise is in radio astronomy if tomorrow there comes a candidate which which re detecting the radio and we are very excited about it. And it turns out that James Webb is the perfect telescope to figure out if there is an exoplanet there we'll use the James Webb space telescope.

Vikram

Optical light is radio waves. I mean, I would say it's still radiation. Right?

Harish

Yeah. It's electromagnetic radiation. It's the same phenomenon. It's exactly the same phenomenon. It's just a different manifestation of the same phenomena and it just different wavelengths. So the FM radio that you'll listen to that's about 90 megahertz, right? And so that just has an enormous wavelength. I mean, the wavelength of FM waves is comparable to, human beings. They sort of leave the size of things. But the wavelength of optical light is measured in hundreds of nanometers, but essentially it's the same physical phenomenon.

Subu

nice. Actually, I want to walk this back a little bit and make sure I understood what you said about how we detect, what elements are there in the atmosphere of an exoplanet. Right? So what you're saying is if I imagine this, right, so you have a you have a planet that passes in front of its sun, right? And when we observe the light coming from there, so. The sun is behind that planet and that that light passes around the planet. Right? And the little bit of light that passes through the atmosphere of the exoplanet, when it hits our sensors you, it has the same effect that the prism has on light and you see different colors in the infrared spectrum, essentially.

Harish

The sensor.

Subu

yeah, it's a prism, isn't another sensor. And so by that, you can see that you have some fingerprints saying that, Hey, if there is oxygen in the atmosphere, then this is how the light would split in our prism, the light that's coming from the from the exoplanet.

Harish

Yeah. Because every element absorbs and emits light preferentially at some wavelengths.

Subu

Got it.

Harish

And so in fact, this was the, I mean, there's, there's an an amazing historical value to this. Just this concept because back in the days people knew this, so people are sorting vapor lamps, and so they could pass that light through a prism or a deflection grating as we call it. And they could see that Sodium Vapor lamp, which is yellow in color. Some of us have used it in high school experiments. It's yellow in color because sodium, when it's excited preferentially absorbs and emits in this case, emits light at certain wavelengths, which fall in the yellow part of the spectrum. So the sodium vapor lamp looks yellow, right? And so people have done that for different things like different elements on the earth. They would just take it that, burn it and see and the burning was just to excite the element. So it, it emits light and see what kind of fingerprint it has. And the fingerprint is just different lines in that spectrum when you split the light using a prism. And so when people did that with the stars and the sun, they saw the same fingerprints. And we take that for granted because somebody told us this when we were children, but back in the days, it was not clear that we are made of the same things as the stars, right. There actually came as a surprise that we are made of just the same things as the stars are made of, of course, somebody took starlight and split it in a prism and this all the same signatures of hydrogen and the different elements.

Subu

Yeah, like Carl Sagan said right, "We are all stardust".

Harish

Yeah, yeah, yeah. We are stardust then. So you get the same signatures because we have made of the same elements. And that was a beautiful observational confirmation that all the things on the earth, which we all knew since antiquity turns out they're made of the same things as everything else, like in the sun or the stars. In fact, that's when sun's light was split in different colors, They want a few lines, which had not been identified in any element on the earth. Okay. And so it was curious, and it was . That element was named after the sun. Sun is Helios in Greece. And so people call that element helium and helium is, is the second most abundant element in the universe where it's very rare in the earth, on the earth. So helium was discovered by looking at the spectrum of the sun. And after that, of course it was separated on the earth. And people realize that it's the element after the hydrogen, in the, on the periodic table,

Vikram

and now we're running out of helium.

Harish

we are. And it's the reason why we don't have a lot of helium on the Earth. It's very light, very easily escapes.

Vikram

And we keep filling it up and balloons and really, yeah,

Subu

Wait a minute. That that's not a joke. Are we really running out of Helium?

Harish

I I mean, not like tomorrow, but there is a concern about a helium, whatever deposits or whatever you want to call it.

Vikram

we are continuously depleting our helium resource and it's a finite supply that will eventually go out one day. Just like a fossil fuel is a finite supply of, fuel now.

Harish

yeah.

Vikram

no more floaty balloons.

Harish

yeah, So it's actually a beautiful example of why we should do fundamental research, because if you set out, if you had set out to find all the different chemical elements, you probably would not have found helium. Right. And so the astronomers were not really, they were not setting out on this problem. They just wanted to understand what sunlight is made of. Right. So that was purely a curiosity based question. But inadvertently, it led to the discovery of helium and helium has a lot of applications. So it just one example of how doing basic research curiosity for the sake of curiosity in the very long run actually gives you something of immense technological or economic value.

Vikram

That's a good segue into, why we should actually study astronomy as a society and what benefit will it have in our life on earth and our understanding of where we came from, right?

Harish

Yeah. Yeah. I'd say interesting question. I mean, I think about this astronomers also discuss this we have a few beers and then when we're complaining about how much funding we get, there's always the discussion of, what is the value of astronomy to society and that kind of stuff. I actually think that at the most fundamental level we should fund astronomy or basic research. I'm going to take the example of astronomy because that's what I know. But I, when I say astronomy in this context, I really mean basic research like curiosity for the sake of curiosity kind of thing. I think we should do that because it is innate human nature to do it. I mean, think about it. Like, why do you solve a crossword puzzle? Like, why do people solve Sudoku, why do people do this things that there's no tangible material benefit of doing it? I mean, it's not going to help you find food or mate or whatever, what people do it because it's in that human nature to try to find problems and solve them and try to figure out what's going on and, mysteries attract people. So at a very basic level, I could even say it's a very ill posed question in the sense that we should do astronomy because we are made to do, like, we are built that way. It's, it's very innate to human beings to do this. And I mean, astronomy is probably one of the biggest mysteries, right? Like, well, what's happening, how does the universe work? Why are we here? These are very basic mysteries. And so I think that's at one level it's you can say it's part of human nature or culture to do this. And that's why, we should do. There's a huge educational benefit. If you want to come to more tangible benefits if you go to a high school and, you want to excite people about science, engineering, whatever astronomy is a fantastic hook. I mean, high school kids love astronomy. We all did when, people love space exploration, astronomy. So even though, everyone who's excited about that, they don't end up being astronomers, but they become engineers. They become, physicists. They, they become any number of things in the technical world and that moves technology forward. It moves human flourishing forward. And so astronomy is a really good hook to, to inspire people, to get into these kinds of fields. That's one reason actually is one of the reasons I think governments fund Astronomy because they know that they're going to get an economic benefit on the other end by doing this stuff. The other thing is similar to if there's a long-term benefit like helium was an example, the many examples like that. I mean, I, we always, whenever we complain about how much funding we get there, there's always a topic that comes up among astronomers or physicists where, it's a thought experiment. Like, imagine that we started patenting, all the things we did, right? So let's say quantum mechanics was patented. So every time you use the concept of quantum mechanics, you have to pay a dollar or you know, whatever that amount, right? Every semiconductor chip that is manufactured. I mean that the working of a, of a semiconductor junction is essentially quantum mechanical. Right? And so imagine if every chip manufacturer, every CCD camera made, if, if the physicist got money, I mean, it's the biggest return on investment. You can imagine. It just that, it takes so long to get that return that the companies are not going to invest in it. So you need governments to do that. If the return came quickly, every company would be on this. Imagine the amount of return you would get if you patent, let's say quantum theory or something like that, I mean, it's an absurd example in terms of, doing it practically, but you know, you get the point, there's a huge return on investment. In the United States, actually in most Western countries, it's just a few percent of government spending goes to basic research. So imagine the return on investment, you get for a few percent, you just have to wait long, but you will get it right. So that's one reason governments invest in it and we as society should, there's also short-term benefit. In astronomy we are solving really hard problems and to solve these hard problems, you need to develop technologies. One classic example that comes from radio astronomy. So I know it is a lot of the algorithms that went into the wifi routers, which we use came from the imaging algorithms we use in radio astronomy. And so that's just a direct technological translation. And so there are many examples like that. The astronomers were one of the first to really adopt CCD cameras for the telescope. And so they played a huge role in developing the technology and a lot of the smartphone cameras use CCD. I mean, nowadays they use slightly different detector. We use the CMOS detector but for a long time, all the cameras were using CCD detectors. And so there's just a direct technological transfer that happens. So if you get a bunch of people who are motivated smart to solve hard problems, they will push the technology forward and it'll have other application. So yeah, I mean, the return on investment on basic research is huge. And I think more people should know about it. How, how big the return on investment is,

Subu

So you were saying, right. I mean, space research is typically a fraction of a government's budget.

Harish

I'm talking of all, all research I'm talking, take the United States. I'm talking of national science foundation, national Institute of health, not just the physical sciences, the life sciences, you put all of that together. I think it will come to a few percent of the federal budget.

Subu

Right. So I'm sure that, I mean, raising $10 billion to build the James Webb telescope was not an easy feat, right. I mean, I'm sure a lot of people struggled a lot to raise that kind of money. And if you look at it from a company's perspective or a 9 billion, actually, it's not that much money considering the amount of benefit we can get. So my question to you is that if you had unlimited money, right? I mean, if a government or an institution is willing to give you, Hey, here's a blank check, go do a build, whatever you want with what, what is in your wishlist? What would you like to build or, I mean, what, what do you need if you had unlimited money.

Harish

Yeah. I think you'll, you'll get different answers if you ask different astronomers. On my wishlist would be to build a radio telescope on the moon and I'll explain why. so I spoke about detecting these radio waves from exoplanets, right. And, and using them to measure their magnetic field. Now it turns out that the information on the magnetic field is in the frequency of the radio wave, which is being emitted. Okay. So I told you that the earth has a one Gauss magnetic field. So the other thing is also powerful radio source and it's radio emission. Kind of peak at about three megahertz. Okay. That's very, very low frequencies. The FM band is about 90 megahertz, right? So three megahertz is very low. Frequency. Jupiter has a much stronger magnetic field and its emission goes up to 40 megahertz. Okay. Still about half of your, your typical FM frequency now from the earth, there is a limit to how low you can go in frequency and still observe cosmic waves from outside. And the reason for that is the earth has a layer in its atmosphere that is made of purely plasma. And that's called the ionosphere. Okay. And the ionosphere becomes opaque below a certain frequency below about three megahertz. The ionosphere is opaque, so we can't see what's going on outside. It's really like an opaque wall. We can't really see. So any radiation below three megahertz, if it is emitted from the earth, comes back to the earth. It stays within the whatever is outside. Doesn't come. So there's just a boundary. There's a wall. In fact that's how the old am radio used to work. When we were kids, we could tune into BBC from England, even though there's no line of sight because of the curvature of the earth from England to India. But that was at such a low frequency that, you just had to randomly point somewhere and send a signal and it hit the ionosphere and then bounce. So anyone in the world could pick it up. Right? Anyhow. What this tells you is that we have the technology, maybe, even though we haven't done it, but in principle, we have the technology to detect radio emission from a Jupiter, like exoplanet. So think of a gas, giant exoplanet, like Jupiter. But eventually you want to, even though that's going to help you a lot, in terms of understanding how magnetic field is developing exoplanets, and you could apply some of that understanding to an earth-like like Rocky exoplanet, you want to eventually detect directly the radio emissions from, earth 2.0, let's say right. And an Earth-like planet around the star. Other than the sun. And so to do that, well, we can't do that from the ground because those waves never reach us. So you have to build something in space. So there are two options you could just build, antennas just floating in space or you could build something on the moon because the moon doesn't have this layer of the atmosphere. Actually it doesn't have really an atmosphere. And so there's, there's some, there is a lot of talk and, design studies and stuff like that. So it's at that stage where we tried to propose that we build a radio telescope on the surface of the moon But it's at a stage where, we are trying to think of the design, trying to figure out what kind of issues we're going to encounter when we'd like to lay this out, lay this telescope out on the moon that kind of stuff. And it's also picking up momentum because a lot of the space agencies want to go back to the moon. There's a big push to go back to the moon. Probably a lot of that is commercial. There's interest in mining, whatever, right? And so we want to get that first as astronomers, because the moment there's huge commercial activity or some kind of an industrial scale activity on the moon, there's going to be a lot of what we call radio frequency interference. So this is all unwanted signals that are just generated by humans. And they're so bright compared to the cosmic signals we're looking at. And so where's one of the problems we have on well, you're trying to observe a really faint cosmic signal, but there just so much emission coming from all the human technology we have all kinds of electronic devices, we use power lines arc sometimes they create some kind of a static noise, which, which our telescopes pick up. So we want to go to the moon before everybody else goes to the moon. And,

Vikram

you've got to beat all these billionaires, trying to jet off in their rockets, get there first and build your

Harish

right, right, right. Yeah. Yeah. So, yeah, we'll see how, how, well, we fare, fare in that. But essentially that's, that's kind of the pull and there you're really talking about billions of dollars of investments. Like, I mean, it's not going to be simple to build a huge radio telescope on the moon.

Subu

So, okay. But talking about man-made noise or human made noise so at one millisecond pulse that you told us about earlier, that could just very well be the intern microwaving his ramen.

Harish

So wait, have you read about this or did you just, no. Okay. So this is weird because one of the things that people were worried about was exactly that.

Subu

Oh God! Really?!

Harish

Yes. Because when the first discovery was made and published, like, there were a few believers, but really they were believing it because they wanted to believe it because there's something new and exciting, but most of us were really skeptical. We should be, I mean, you should always be skeptical about your discoveries, but it turned out that if you prematurely open the door of a microwave oven, when, you know, when the magnet, the source in the microwave is still on, if you prematurely open it, it creates a pulse which looks kind of similar to the fast radio bursts, we were talking about.

Subu

Oh,

Vikram

That's amazing.

Subu

you go.

Harish

Well, this source of radiation was identified and it was identified because this kind of emission peak during lunch hour near the observatory and using people figured out that this is not cosmic, but it turned out that the cosmic signals were real. It just that this particular human made interference could masquerade as one of those bursts. But, people could isolate that and the cosmic stuff was actually real

Subu

look, you, you called it. If someone, you, you said you called it when someone prematurely opens the microwave over right. In my book, that's the only way to open the microwave oven because I never let it go all the way to time zero when it is running. I usually, I let it go for, there's a, there's a button that says run the microwave for a minute. Right. I click on that, but I need it only for 20 seconds to warm up my food. So at 20 seconds I just bang it open.

Harish

So it's because of people like you, a lot of astronomers had to spend taxpayer dollars trying to figure out what the hell is going on.

Subu

That is hilarious.

Vikram

It's funny, always take radio astronomers seriously. I don't know if you've seen the movie don't look up, which was recently released

Harish

I it's on my to watch list. I saw it had bad reviews, so it kind of put me off.

Vikram

No, no, you should totally, you will appreciate it. because these are these two, astronomers. They're not probably radio astronomers, astronomers who are really like nobodies in the field and they are watching the sky and they find that is a meteor going to hit earth and obliterate all life on earth. And so they try to alert everybody and they get the whole movie is what happens when they try to alert people. It's not like, like an Armageddon, not Armageddon. Which movie was the Bruce Willis one escapes my mind.

Subu

doesn't, it is Armageddon. It is Armageddon.

Vikram

Oh, Yeah. Yeah. It is armageddon. They send up rocket and the nuke, the asteroid into bits. Yeah. So that is probably not the way real life is going to go. Don't look up without giving away the spoiler is probably most likely what will happen if you go tell the government tomorrow, there's a meteor that's going to hit.

Harish

Most of the scientists are a skeptical bunch. Okay. So if, if you know me or some astronomers find something like that, the other astronomers won't immediately believe it. They would want to confirm independently. Anyway, that's a nice kind of skepticism. I, I think you're talking of a different kind of

Vikram

Yes.

Harish

just blatant disregard for some kind of scientific evidence.

Vikram

Among a whole lot of other things. watch the movie.

Subu

Yeah. Okay. So, before we wrap up this, the technical segment of the episode, right. I have a couple of philosophical questions for you.

Harish

oh, I like philosophical questions.

Subu

So yeah, having stared out at space for as long as you have, right. And looking at all these planets do you think we're alone in this universe?

Harish

oh, I always get these questions when I speak to usually journalists. I mean, I'll give you a banal answer because I'm, as a scientist, I have to be frank, I really don't know. I mean, there's no way to know. There is simply no way to know anybody who says that they know one way or the other is, is, it's not right there's, there's no way to know. Yeah, I mean, you could, a more interesting question is what do you want to be, want to be true? Like they want us to be alone or, that's a, where you don't need an astronomer to answer that question. Like we are

Vikram

I just my, layman perspective of that is given how many stars that are and how many solar systems that are around those stars. There is an extremely slim chance that we are actually alone in the universe.

Harish

Right. I mean, astronomers must have played this game. I think it's called the Drake equation or something like that. And so you say, oh, it's all a little, hand-wavy like, we don't have solid numbers for this, but you know, we know how many exoplanets there are, you can calculate the fraction where the planet isn't too hot or too cold. And, you can keep doing that. Right. And you get to a huge number because you're right. I mean the universe is absolutely enormous. So there are just the number of, the number of planets is so big that this experiment has been run, an enormous number of times. But what we don't know is what is the probability that life appears, right? We know it's small because we know that, it's not like everywhere we look in the solar system there's life. So we know that number is small. So in the end you're taking a huge number, which is the total number of planets, which have the right conditions. And you're multiplying that really small number, which is the probability of life appearing. And then you are asking what the answer is, is the answer one or more. Right. And so it depends on how, how big or how small these two numbers are.

Vikram

There is the other problem, right? Imagine there is a planet with life on it, like ours on the other side of the solar system. I mean, off the universe somewhere, I don't even know how you define a site. There is no up down somewhere. No, the, by that far away. by the time we even have any form of communication or anything from a place like that, it's virtually impossible because the fastest thing we know is light. And even that takes trillions of years. The chances that we live in communicate is almost none, right? There is no medium of communication

Harish

I mean, you don't have to go that far. I mean, let's just go to the other side of the galaxy. We are in right I mean that galaxy is know I'm roughly quoting rough numbers about a hundred thousand light years across. Okay. So let's say there is a civilization that wants to communicate for a hundred thousand light years away. I not own galaxy, which is literally our backyard. Like, so every time you send a signal and you have to wait 200,000 years for the reply, right? I mean, compare that to a human or even a civilizational timescale. It's just huge. And so, I mean, direct communication unless something is really close to us on, on like a human or the civilizational, timescale

Vikram

it could argue it's like a species, right? I mean, an entire species could wipe itself out in 200,000 years. I mean, the homosapien may not exist in 200,000 years, so,

Harish

Yeah, that's possible. Yeah. That's possible that, it, it turns out that maybe there's some basic fundamental limit to how long life can exist. Although, I mean, it's quite long. I mean, life has existed for billions of years on the so it's, it's quite long, it's probably going to be quite long.

Subu

Okay. Give us a glimpse of what it is to be you. Can you tell us what you find most fun in your work and maybe some experiences from your travels around the world?

Harish

There's always the fun thing of making a discovery, you know, waiting for the image to appear on your screen and, just the thing you wanted to see and you see it and you're all excited, but may, I mean, there are more, there are things more specific to an astronomer. I think I think it's kind of fun to say. One of the things is a lot of the telescopes are in really kind of an extreme or a fantastic environment on the earth. There are telescopes on an extremely high plateau in Chile. There are a lot of telescopes which are at very high elevation. I mean, these are all extremely beautiful locations. So one of the telescopes I worked on it was even before I started my PhD, I was working at the Raman Research Institute in India then was it's called the Murchison widefield array. And it's a radio telescope that was then actually being built in the Western Australian desert. And, why would you want to build in the Western Australian desert? Well, because there are no humans there. I mean, there are, but you know, very few the population density is, as low as you can imagine which means there's less human generated interference, right? And so you build a telescope there, and back in those days, there was literally nothing there in the desert. There were just these antennas lying on the ground with cables and we used to go and expeditions. So that would be a bunch of us packing up all the, the, see what equipment all the digital electronics onto a pickup truck and then driving for, 10 hours or whatever it took from Perth to get to this completely middle of nowhere place and spent two weeks there collect data. And then we had a big diesel generator for electricity, collect data and then pack up everything and then drive back. And so I went on one of these expeditions and he was absolutely fantastic. I mean, this is as much as in the middle of nowhere as you can get it was blistering hot and Australia was. So it was very surreal. I mean, the flies in Australia the nastiest I've ever experienced. So if a fly finds you, you can't get rid of it. You just can't get rid of it. You can only work with like a kind of a net around your face, but if a fly finds you, you can't get rid of it. It, it just wants to come and. I don't know, like suck water off your, off your eyes or something like that. And you can't get rid of it. You run away, I'll come with you. You go wherever. Once it finds you, you can't get rid of it. So that was, that was a very interesting experience. We saw this huge lizards, which are in the desert. We saw kangaroos of course, emus. I learned that emus and kangaroos are more dangerous than what I realized especially emus. I mean that enormous, they're absolutely enormous. You know, the The first time you see when you're really not ready for how big this bird is. And so we used to have a long day come back. There was a little homestead that a family living there, they had a little plane, like one of these tiny planes, people fly for a hobby and they used to fly in that plane to visit the neighbors for dinner. That's how far apart?

Subu

oh,

Harish

I mean, there was no roads that like the road going from Perth was just a dirt track and you would drive off to get that with the pickup truck. So we used to come back, there was a deck, sit there. Chat have beers and it was a desert and it's pretty flat. So you can actually see the sun go down. And, actually saw with my eyes, the quintessential Australian view of your you're in the Outback, you're seeing the sun go down and in front of the sun, are this hopping kangaroos, like it was, it was beautiful. So, astronomers are, quite fortunate because we get to go to, really beautiful places to work on telescopes to, to take observations. It's really, it's a privilege to be able to go to these places.

Vikram

I have a joke that, an astronomer like yourself. will appreciate, and maybe you, if you go on one of these desert expeditions, you will remember my joke. Do you want to hear it?

Harish

Yeah, yeah. Go

Vikram

So what happened was there was this government, the government was emulating the surface of an alien planet. And they had these people as astronauts who are walking around in the desert, because they were trying to emulate and get people used to, an alien landscape kind of thing. So while they were doing this whole experiment and, walking around in the desert, they run into one of the local, people who live in that region, right. And that person comes down and they find somehow communicate to them and ask, they, they say who you are and all that. And that person says, I live here, whatever. And he asks, what are you guys doing? And they say, no, look, we are actually going to this practicing to go to a, another place like the moon, like, if we have to walk on the moon, we practice here. And so this this person gets a suddenly in awe. I says, oh, you're going to the moon. That's where my gods live. So I want to, that's great. You're going there. Hey, if you're going there, can you tell them something that, I'm going to tell you, and I want to tell them something from my people said, okay, sure. Tell us what it is. And so he tells them a phrase that he has to tell the people that God's on the moon. Okay. These people memorize it. They write it down. They Go back to their base or whatever it is. And they're like, oh, they tell the other people at the base look like this person we ran into is given us a message to tell somebody in the moon. And everybody goes like, what is this message? What is this message, so they get an expert and all those things, they have, the, whatever they somehow decode the message. And then the person who decoded it. starts laughing. Everybody's like, why are you laughing? What happened? Like, you know what? This is, it says, these people are here to take your lands runaway.

Harish

Yeah. So another telescope anecdote. So this happened when I was in Caltech. We had some observations planned on an optical telescope and that's on Palomar mountain. It's not far from where Vikram is. It's not,

Subu

is

Harish

um, isn't yeah, there's an observatory it's run by Caltech. And so I went there, it was with my then mentor, who was a very well-known faculty at Caltech. He actually, he was born and brought up in India he is now faculty there. So it was very well known, senior astronomer. And so maybe he felt that, Harish is this, radio astronomer trying to do break into optical scene, optical astronomy scene. Maybe I should take him once observing, show him how things are. By the pro. So we bought, drove in a car, we went to Palomar mountain, we prepared for all the observations calibrations we've made lists of, you're do a lot of preparation before observations. So we did all of that. And then at every optical telescope, there's a person who is kind of whose responsibility is to ensure the safety of the telescope, because the astronomers are always going to do something, either desperate or ambitious. And you want one level-headed person whose job only is to make sure that the telescope is fine. Right? And so there should be no water that falls on the telescope. When, when you reach the dewpoint, you need to close the dome, that kind of stuff. So we went there, it was a clear night. And so we thought we'll have observations. And then this person's like we can't open the door. And really what do you mean? It's a clear night? Why can't we open the dome? And this person said, because there's snow on the dome and protocol is if there's snow on the dome, then we don't open the dome because it had snowed the previous day. And then I realized, well, actually that's true because if during the night the snow melts or let's say moves, part of it can fall in if you open the dome and fall on the mirror of the telescope. Right. And that's a big problem. So I said, okay, we can't open. So we waited there for an hour. And at some point this person told us, I don't think we'll open the dome tonight. And this happens when you go, when you do optical observing, because optical observing has to happen in the night. You can do it during the day. And Radio Astronomy is nice in that you can observe whenever it doesn't matter. At night, day, rain, we're observing, Sun, we're observing windy. It doesn't matter. We always observe. Anyway, optical is not like the clouds have this kind of problems you don't observe. So what do you do? So I didn't know. It was the first time I went optical observing. I thought, well, you just go and then you go to sleep. I mean, what is supposed to do? We had quarters there. We had rooms there. And so this professor to my pleasant surprise was like, no, no, that's not what you do. So come here, sorry. It takes me to the basement. And there's like a drawer that and he has a stash of whiskey there for nights when you don't get to observe. so we sat there and drank whiskey,

Vikram

So life as an astronomer is not always that bad.

Harish

no, no, it's a lot of fun. I mean, it, it gets difficult also because if you're observing during the night it can be difficult if you have children. And then, you have to be a functioning adult the next day. But it has its charms as well.

Vikram

So now that we have spoken about all the cool science stuff, we should go into some part of your journey to become the radio astronomer you are. What does your life look like? I mean, it, you've got all these amazing stories, but basically how has your daily life, like, I mean, just to give an idea to people listening, what it is to be you.

Harish

sure. I mean, daily life, of course, like in any other profession looks more way more mundane. And then what, you might imagine, grass is greener on the other side. So maybe the quintessential view is that, we are always excited about some discovery that is happening in front of our eyes, but daily life is pretty mundane. In the sense that a lot of the time is spent in just banging your head against a code that doesn't compile, for example, right? So you're writing some code to process data, and then it doesn't compile or, if it spits out garbage and you're trying to debug it. So a lot of, a lot of research work is like that, which is, you look at data and then it doesn't make sense. You're trying to figure out what is wrong. And so it's, it's more down, down here, like close to the earth and mundane, and then it's not like. Spending all day in smoke-filled rooms discussing, big philosophical questions. It's a lot of painful, that kind of stuff. A lot of bookkeeping, that kind of stuff. We're at a, at a level about that. If you're a PhD student, then most of the time goes in just doing research. So usually you have a problem towards which you're working. And so you might write proposals to telescopes and these are called observing proposals. You would describe your idea and you would describe the kinds of observations you need. And they would be evaluated by other astronomers. So we also sit on panels, which evaluated the proposals by astronomers. Cause you have telescope time comes at a premium, right? So you have to decide who gets how much time. And then you would get the data and then you process the data. A lot of the work or time also spent on writing papers because that's the end result for us. So, we always say our, our coin is the publications and the citations and that kind of stuff. So the end result has to be a publication. So a lot of time spent in writing papers. We also referee other people's papers. So papers are sent to us. So we have to referee the papers. So you try to understand what's in the paper, try to find any mistakes in the paper, a lot of travel to conferences. It's not atypical for for an early career astronomer to travel to multiple international conferences every year and sort of, prepare to present in those conferences. So yeah, a little bit of teaching when you're, when you're a PhD student, you do less teaching. So at my level, when you're a faculty then it's all of this, but on top of it I also write grant proposals. So there are these huge funding agencies, like the national science foundation in the United States. We have something similar here in the Netherlands and under the European union level. And so you need to raise money to do your research, right? And so once you come to a faculty level, you become a little bit of an entrepreneur in that you might have a great idea, but if you can't commandeer, the resources to implement that it's never going to happen. Right? And so you need to commandeer resources in terms of computing resources, you need a lot of the projects. We do need super computers. So you need a lot of money to procure those computing resources. You need to pay PhD students and postdocs. So you need salaries for that. Maybe you're going to hire engineers to design the telescope. And so you're gonna have to pay their salaries. And so where does all the money come from? A lot of that comes from competitive grants. So I spent quite some time writing these proposals to these funding agencies and right now, the proposals. I'm aiming or get there to the tune. Each one will be to the, something like a million US dollars, like, and so that's a lot of money and it's never going to be given away just like that. It's a big sum of money. So there's a very rigorous review process. So you spend a lot of time perfecting your proposal and you also spend time reviewing other people's proposals. Like, and so time goes there. And when you're a faculty, there's more teaching. Of course. So there's teaching you have PhD students. So meeting with PhD students discussing with them, not just the project they're working on, but also kind of motivating them because sometimes students also get de-motivated because research is hard. I mean, you spend, you can spend a year and not make progress is possible. So it's very natural. It's human to get de-motivated. So try to figure out, how can you motivate them? Thinking about, where their career is going. They need to also find jobs like after they finish their PhD. So thinking about that, so a lot of the time goes also in networking. You're thinking about what is a good fit for this student for, for the temperament he or she has for the skills he or she has trying to send them to conferences or for work visits, which will increase their chances of getting an academic job. So, generally thinking about their careers. So, so things kind of shift from doing just research and a little bit of teaching to doing that. But a lot of these other auxiliary things around university, life or academic life the universities are also bureaucratic. There are a lot of committees, there's a curriculum committee, like, there's the university politics, where there are humans, there's politics. And the committees are like that, the physicists are not happy that we are teaching this course, that kind of stuff. So as we become a little more senior in, in senior faculty, you deal with that kind of stuff as well, the running of the general university administration. Yeah. So this is, different facets of an academic life.

Vikram

Awesome.

Subu

So, you you've done research at premier institutions in three different countries, right? Raman research in Bangalore, India Caltech here in U S and Groningen, in Netherlands. Could you talk about how research is and how the scientists and the temperament are across three different countries, three different languages. Is there anything particular that you remember.

Harish

I think there are more similarities than you would naively think. Astronomers travel a lot either to go do observations at different telescopes or conferences. So even at the Raman research Institute in Bangalore. A lot of the people I worked with had, for short stays, like, for postdocs, let's say a few years being in Europe or in the United States. So because of all this mingling, there's kind of a how do you say common culture that has developed? So in that sense, it's, it's more similar than you would imagine But of course the, research in India has an Indian flavor and some of that has to do with just cultural things. Some of it has to do with how funding is structured in India versus here. So I felt that India was more laid back. So at the Raman Research Institute, things were a little more laid back. It was a more how do you say like an idealistic view of academic life, where you would take long walks through the Institute and think deeply about problems and, it was a, it had a little bit of a flavor of that kind of idyllic academic life kind of, feeling Groningen and especially Caltech, it did have that aspect of it, but Caltech was way more on the edge. It's like, let's go, let's go. Let's go. Like, what's the next big discovery? It was more intense. And so one of the things which is important is also to match your personality with the culture of the institution. Like, I mean, and so you had a very intense person want to make it big you're better off at Caltech, but if you're more of a laid back, person wants to think deeply about a problem for like few long years. I'm kind of generalizing here. I'm probably exaggerating a bit just to show you the contrast. It's, it's a generalization and an exaggeration.

Subu

Okay. Yeah. I mean, is that like, is there more say administrative overhead in Caltech versus say in Groningen and I mean, is there

Harish

Well,

Subu

of,

Harish

I think it's a private institution, so it's the place I've been. I is the least administrative overhead I've seen in a research institution of the places I be in there. Just because Caltech is private.

Subu

yeah. Because the reason I specifically ask about administrative overhead is because, Richard Feynman, right? One of our favorite physicist. And if you look at all the stories from two of his books, surely you're joking and genius. There are a lot, they do bitch a lot about, oh man, I was asked to teach this course and I just didn't want to do it. I just wanted to stick with my research. And it seems like researchers in general want to be left alone. And anything to do with administration is like taking a time away from what they really want to do.

Harish

Yeah. So administration is universally hated quite strongly by most, the research types, the academic types. So it's seen as a necessary evil something you have to do teaching is a little more nuanced. I think people do tend to complain about teaching loads and things like that. But I think it's different from complaining about administration. I think deep down the researchers also most researchers do see that teaching is an integral part of academic life. There are exceptions, of course. So I think teaching is, yeah, you might complain about it, but it somehow feels like part of academic life. Like it, it doesn't feel like I'm doing this completely worthless thing. Different institutions have different different breakdowns. So for example if you work at Astron, which is the Dutch Institute for radio astronomy, that is a national research laboratory kind of, so think of some kind of a us national research lab. I dunno, maybe people have heard of Sandia labs or people might have heard of Pacific national laboratory. These are directly research, only laboratories. They're not, they're not universities like, and so in these places, the teaching load is low. Some, most people, you can actually go through a career if you're not teaching at all just doing research, but you will do what is called service, which is maybe you would help in maintaining the instruments they have, maybe it would help in other scientists using the instruments or writing software for those instruments. Right. So nobody has a hundred percent of their time to do whatever they want. I mean, that doesn't exist , at the University you have to teach and be part of the administration, if you're like a national lab or something like that, then you will do research, but you'd also do service because every national lab is there for the reason. And it probably has a big facility. It has to maintain, which is actually good. You want to take your mind off. thinking too much about something can be a bad thing. Like, and this kind of small distractions help you take your mind off research teaching, especially as fantastic because when you teach, you're really going back to the basics. Right. And so when you prepare for teaching, and this happens to me quite routinely, when you're, when you're preparing for teaching you're, you're usually teaching some very fundamental concept and then you realize that, wait a minute, I never thought of that. We always made that assumption, but what if that is not true? Right. And so it turns out that everybody made that assumption because for the kind of things we were doing, that was always true. And so it was just in the air or in the water. Like everyone just made that assumption because, we had never seen a contrary example, but maybe there's some new research that shows that if that assumption is not true, then it has a profound consequence. Right? And so teaching really gives you that just an example of how teaching really makes you a better researcher. So I really believe that teaching makes you a better researcher. It really gives you new ideas. When, when you're preparing for teaching, you come up with some new ideas for research.

Vikram

That's awesome. No, now that you teach so much more than you've ever done in probably in the rest of your life before this. how do you contrast it to the time when you were a student in India, going through an education system we all went through, what do you think can be better now? Or what are your thoughts on that?

Harish

Yeah, I think so I went to education in India up until I finished my bachelor's. So I went through a pretty run of the mill school. Even in high school, I think it was, nothing fancy. And I started engineering for my bachelor's. My views are pretty mainstream in that we all know that Indian education was too much by rote. It was not really about, deeply understanding things. I noticed that, of course I definitely noticed the difference and, things are getting better in India now, but when we were students, it was like, this is what you're supposed to memorize for the exam. And that's good enough. I mean, if you, if you have more questions, that's fine, but this is good enough. This is what is expected of you kind of thing. So it was very boxed in, you're expected to know this, this, this, and this, and reproduce this, this and this in this particular way in the exam. Which is unfortunate. I mean, that's not very good for learning

Vikram

not very inspiring as well, because

Harish

Yeah, it's not really,

Vikram

is if this is what is learning, then people are put off from learning for the rest of that life, which is actually the worst possible consequence out of an

Harish

it.

Vikram

system.

Harish

And I think we were also lacking, I now feel that we didn't really, or at least I didn't get a very good education in the humanities as I did in more technical things. I think that was a really kind of, I mean, the way we learned languages was I only realized much later in life that that's not how you're supposed to look at languages. You're supposed to learn read prose poetry, comment on it, write a commentary on, some piece of work by somebody and, we never did that kind of stuff. Right. And so I felt that I lacked that I've tried to develop that later in life. But you know, nothing beats getting a solid foundation when you're the child right. And so I've tried to develop a habit of reading and thinking about, fiction of nonfiction and, discussing it with other people commenting on it. But I think that was lacking. I felt that in terms of what was good, I think we had a very idyllic childhood. I think that was fantastic. We lived in a place with fantastic weather. We were out all the time. very outdoorsy. And I think we grew up in a culture in the school and even outside, which was a very, very nice for children. We got to spend a lot of time playing with other children,

Vikram

we grew up in an era without screens either. Right?

Harish

yeah, without screen. So, I just remember, like, I, I visited my family recently and we lived for, from the time I was in the fourth standard to nine standard. We lived in one apartment in Bangalore. And we were just remembering the time when I realized that I actually don't remember what my house looked like, because I was never at home. I only went home to eat and sleep. Right. I was either in school or playing outside. And so I think that was fantastic. And even in the education system, even at schools, I think the, the social life was fantastic. The teachers actually really cared about you. They were quite approachable. I mean, I was really afraid of some of them because we also had corporal punishment, unfortunately, which I don't appreciate, but many of them were, really like, very friendly towards you cared about you. And I, I felt even loved by some of my teachers like, and that was very nice. It was a very kind of a community. Nice community feeling. Yeah. I think we are very lucky to have that coming to engineering. I actually looking back felt that the syllabus we had was actually quite good in engineering.

Vikram

Yeah. Why do you say that?

Harish

I actually think the syllabus was good, but I think the structure of the education was vocational, but the syllabus was more academic. You know what I'm saying? Like the way the education was structured and, and the end goals of the education were really vocational. Like what we would call a Polytechnic. Right. You acquire a certain kind of skill. So you get a job, right?

Subu

yeah, like a trade school.

Harish

Yeah. Like a trade school or something like that. Like in the Netherlands, we called them a university of applied sciences or something like that. Like, and so, but the syllabus was brought academic.

Vikram

Okay. Okay.

Harish

I think we had a little bit of a mismatch there because the syllabus was kind of a academic education, but the way everything else was set up was how you learn this, this and you know, you learn programming, you learn, I don't. Know. Like VHDL like the hardware, language to program hardware at the lower level. you know, you learn these kinds of things. The companies are going to come and you'll get a job. Right.

Vikram

Yeah.

Harish

But I think there was a mismatch that, and I think that's something that can be improved. I uh, I think most people wanted that vocational aspect. Really. I think that most people didn't really care for you know, the academic, which is fine. I mean, you don't want the entire population going through some rigorous academic system. Like, I mean that, that's not for everyone. Most people are happier with like a learning a trade and then getting a job. Uh, I dunno. I dunno if you guys felt the same, but looking back, I felt that we really should have been a vocational school.

Vikram

good observation. I did not think about it till now, since when you mentioned it, but you're right, because people did all that education there to get a job and not so much to learn the matter for itself. Right. But the syllabus was nice in the sense that we were introduced to a little bit of everything and gave us a taste of what we wanted to go and pursue. So in that sense, it was nice.

Harish

yeah. Yeah. I I'm quite happy with the syllabus. But I really felt the environment was more vocational.

Vikram

So as zooming, now that you've seen, yourself as a student and as a professional astronomer, what would you say that it takes for somebody who is starting off in high school or college or something to pick up a career in science, fundamental science or radio astronomy, and what temperament you need to do that?

Harish

Sure. Yeah. I think the, I start with the hardest thing. The hardest thing is to figure out where you really fit in. It's very hard for a young person to do that. So I would first say you need the right mentors because looking back at my own life, it was close to impossible for me to figure out what was really, what, what was I good at? What was my temperament well-matched to do? It's quite hard for a, for a teenager or someone to figure this out. So I think you need the right mentor, but let's assume you have some mentor who can give you the right advice. , What kind of person should you know, or what should you, what do you want to do to go or to get into science or scientific If you want to go into physics, astronomy, these kinds of disciplines uh, you could go the route I went through, which is through engineering, but that's the harder way to get there. I think you're better off learning physics. A lot of astronomy is basically physics applied to celestial bodies, right. And so I really missed out. Some very basic physics courses, I, you know, I studied engineering with you guys, so I never studied quantum theory. I didn't study special relativity ideas, I didn't study general relativity. you know, these are the things, you know, I use day in, day out, like in my work. So I had to pick that all up by myself. It did give me an advantage that knowing engineering will really help you understand telescope data better, because you can really figure out what problems are there in the data, because you have a basic understanding of how these things work, because you're an engineer, but I would say it's the hard way. So you're better off learning physics for your bachelor's. And master's, if you want to you know, this kind of academic route into astronomy or in physics that said, I think you're, you also need to make sure that you somehow get into a good physics or program. , And there are not many in India. So if you're in India, then you really have to do whatever it takes to get it to not any degree in, in science or in physics, but right. To get to, a more reputed or, or a good institution, simply because even if you're even, let's say some people are really talented, they're good. They actually don't need teachers. They can be, they can really do all this themselves, but you do need the right mentors. Right? And so for that reason alone, you want to be at a, more well-known place, which has more exposure. So the faculty also has a larger exposure. So they. can be better mentors. And then, for any research career, a PhD is must, so you have to do a PhD. , That's really, the stepping stone is actually the, the time when you really learn how to do research, you learn how to, formulate a problem because, you know, you can't just say, I want to find, find out the fundamental truth about the universe. That's not a well-formulated problem. That might be the inspiration, but you need to learn how to formulate a problem in a way that it leads to an answer, right? So if you formulate the problem the right way, you're really halfway to the answer. So you really learn how to formulate the problem and how to really push the boundary of human knowledge just by a little bit. So think of the PhD, as, if all of human knowledge is a huge circle, you go to one part of the circle and then push the perimeter by a little bit. And that's the PhD, right? And so like learning to do that is you need that. And so you have to do a PhD in terms of what kind of like, should I be a scientist? Like what kind of skills are required? At least for physics and astronomy, you have to really enjoy doing analytic things like mathematics. You have to enjoy this kind of stuff there's no other way you have to be a little geeky and then. Uh, You need to get a kick out of, doing little physics experiments, trying to figure out how things work So you should have that natural drive. I would say that's a must, in terms of personality, persistence because most of academia is a long string of failures, because most things you're going to try will fail. , So you need persistence grit. I would even say grit. You need to be a little gritty to be able to , to be able to face all of those failures and keep going. , So that's kind of the personality trait I would look for. And it does also help if you're a little entrepreneurial and that really helps when you get to the faculty level, cause you need to convince others uh, and you need to convince the funding agencies to be able to commandeer the resources. You need to be able to sell your idea that's not a fundamental requirement to do science it's a requirement to navigate the system. We have set up. The way funding is organized, the way everything is arranged. And so you need a little bit of that. , But most of all, the most important thing is you just need to be very excited and passionate about, just physics or astronomy or, the field you're in. And, and I would tell people like, look to your own life or your past, like, what were the things, which excited you, where did you spend all your time? What was the thing that you were doing, which made you lose a sense of time, , What could you do for hours and forget what time it was. Like, are they related to physics? Are they related to astronomy? It doesn't have to be exactly astronomy. But are they related to generally the physical world or the physical sciences? Figuring out how things work. Yeah, that's what, that's the advice I would give? Just one more thing I can add is in terms of career prospects, it is not easy. So it's good to go in with your eyes wide open, up until you finish your PhD, your career prospects are perfectly fine in the sense that PhD students, even if they don't become professors or stay in academia, do fantastically well in industry. If you have a PhD in physics or astronomy or related field, you will do very well, in industry. But in academia itself, I mean, academia is not, it's a very big target in terms of, jobs. Right. And the example I always give my students is, I mean, look at a typical professor in his or her life, a typical professor in physics or astronomy has maybe 10 students, I'm just giving you an average number. And the number of professor positions is not growing exponentially. Okay. So it's not like you're going to, you know, just like the virus we've learned about exponential curves after COVID-19, so it's not like every professor, 10 students and the 10 become professors produced 10 of their own. It doesn't happen. I mean, the growth is either flat in the Western world or slowly linearly increasing. Right. That's linear. It's not exponential. So the upshot of exactly. So they hadn't done enough yet. , And so when the professor retires dies, whatever one out of those 10 students can take that position. And so nine out of 10 people who do a PhD, you know, I'm giving you an order of magnitude. I don't know if it's exactly nine out of 10, but it's order of magnitude is right. We'll go into industry and industry loves this people because they're a little different from the people who have just done a bachelor and gone into industry because the people who've done, a PhD have learned how to advance the frontier. a little bit, they've learned how to take a hard problem, formulated in a way it can be answered, break it into smaller parts, which are easier to tackle. And so that skill is pretty important. So there are a lot of industry positions where they prefer people with phds.

Subu

we spoke about this exact thing in our episode on a career where we spoke about, even in say, if you take like a California and the bay area, or you have companies like Google and Facebook and everything where they do need two kinds of workers, they need the engineers who have done their bachelor's and master's who can come with a predefined problem. They need to execute it and get it done and working in the next six months or a year. But they also have. A good set of problems, which they don't really know what the question is. They'd haven't even formulated. What the question is. So they need people with a PhD or people who are experienced in doing research who can come and attack these kinds of problems

Harish

Yeah, absolutely. I'm going to give you a good example. One of my, friends, he did a PhD in physics and for his PhD. He built a pretty sophisticated equipment to trap atoms. You can study what they do more easily. Right? You do things to them and you poke and prod them and see what they do. , And the way they did that was using lasers to trap items. So this person had a very deep understanding of how lasers work, how these kinds of the optical devices work, which handled lasers. And he found a job in a really big company. I think it was facing and the problem they were trying to solve as they were trying to, see if you could, you could transmit data optically, right? I mean, just think of providing internet to a lot of people, but you want to do that optically. Right. And so how do you take a optical beam of light, from let's say a moving platform and couple it into a single fiber optic cable. It's a very hard problem to do this because the beam wanders. Right. And so he, they got him to solve that problem. And so these kinds of problems where there's no obvious solution there, we know of people, do you know, the companies also prefer to have people have done PhD. So anyway, my point is, do a PhD if you love research, but going into the PhD with the attitude that I'm going to learn how to do research, right? And so dont restrict yourself to. I just want to become a professor maybe that's not the best thing for you. You have to be this kind of entrepreneurial thing teaching, maybe you don't like teaching, maybe you don't like mentoring students, maybe you don't like university administration. Maybe you don't like to spend a lot of time writing grant applications. Right. And so it's not for everyone. You also need a certain temperament and, you'll never regret doing a PhD. That's what I always tell people.

Subu

So I, we can't let you go without asking you about books, right? I mean, you've got a really well read person and especially, it doesn't matter if it's fiction. Books, you have a phenomenal books that you read in the course of becoming an astronomer. Do you want to give us some of your favorite books of all time?

Harish

Oh, wow. I've read all the Feynman books. I mean, they were kind of interesting and I, and I enjoyed them. Carl Sagan's books

Subu

Cosmos. Okay. Yeah. Cosmos is one of my, one more of those books, which had a profound impact on me, in high school.

Harish

Oh, okay. I did it much later in life. Yeah. I wouldn't say I'm very well read. Actually, you guys definitely read more books than I did. yeah, so Carl Sagan's book was quite nice. There are some popular astronomy books, which, you know, it's, Stephen Hawking's books,

Vikram

a brief history of time,

Harish

That was interesting.

Subu

Okay. Anything else? Esoteric? I mean, is there like, a book, maybe like an astronomy textbook that a regular person, like us would never touch, but it's worth looking at.

Harish

actually if you're an engineer. You already have a lot of background, in astronomy, so I could even, like, I dare say I would even recommend the books we give, first year undergraduates. Yeah, there's one part, the physical universe by Frank shoe, that's kind of a, that's kind of a typical textbook and it starts at a pretty basic level. So I think it's a good textbook. If you already have some, a degree in let's say physical sciences, so you've done engineering or you're done physics or something. I mean, high school knowledge is all that is necessary to get starter.

Vikram

Nice. I might read one myself.

Subu

Yeah.

Vikram

Why

Harish

It's a pretty big book. It's a pretty big tome.

Vikram

Okay. I'll read maybe 20% of it.

Subu

Yeah. I did. I read the preface and the introduction.

Harish

Yeah. I really, I really enjoy kind of these kind of technical books. I enjoy books where they kind of take something simple and do a simple calculation. Like I really enjoy that. So my PhD advisor once gave me a book. We were talking about climate change and sustainability and that kind of stuff. And he gave me a book called. I think it's called sustainability without the hot air And so this is a book where I don't know if you guys know about it,

Vikram

I've not heard of it

Harish

yeah. So in every chapter he's like, okay, let's just try to calculate how much energy we could produce with written bips. Right. you know, he, so he goes through all of the calculations. He first goes through the calculations of how much energy we consume and the calculation of how much energy we could possibly produce and then uses some really simple first principles calculations to come to pretty important conclusions. And I think that's what I really enjoy. And I learned that from one of my PhD advisor. He was Fantastically good at just doing first principles calculations. And I enjoy things like that. So I fall, if people like that, I would like, even though it's not astronomy you know, it's it, if you like physics, you will, you'll like this, I think.

Vikram

without the hot air.

Harish

Yeah. Yeah. Sustainable. Yeah.

Vikram

So after all this, you probably regularly give your students reading assignments, but on this podcast, we are going to give you one, you need to Go and read the Martian by Andy Weir. We talked about it. in the podcast before,

Harish

uh, Based on which the movie was made

Vikram

Have you seen the movie?

Harish

I've seen the movie and I really

Vikram

Yeah. You should read the book because you know why? Because all the engineering details and the numbers and the calculations yet you just mentioned cannot be depicted in a movie and the book it's like way better

Harish

Yes. I've heard that the book has all of that. I think.

Subu

Okay. Actually, why let it, I'm going to give you a reading homework. . So after, after the the S the same author, Andy Weir, so he wrote this book called hail Mary. I think it is really, it may just be my number one or number two science fiction book of all time. Right.

Harish

Okay.

Subu

and, that is

Harish

Isaac Asimov's classics.

Subu

well, okay. It's a hard one. Okay. Let's say let's call it top three. Okay. Because the reason, the thing, and this is coming from from a person who pretty much only reads science fiction, right? No other, like it's either non-fiction books or science fiction, no other kinds of fiction. So in hail Mary, right. Humanity has to travel to the neighboring solar system to figure out of a problem that they're facing in order to save humanity, and they worked through all the mechanics and a lot of the stuff I don't want to give, give up anymore, but it is it's pretty incredible actually, that there are diagrams of the spaceship they built how exactly each chamber was and what they used as fuel and all kind of stuff. It is, I would say it is even better than the Martian.

Vikram

it's on, it's on, let's meet up

Harish

book.

Vikram

and take notes.

Harish

Another couple of books came to mind. I actually received a fantastic set of books by different people who came to my PhD defense, and each one really left an impression on me. One of them is called the birth of a theorem,

Vikram

yeah. By the French mathematician, right?

Harish

The French guy who won the Fields medal, Cedric Villani , or something like that. It's a little weird. The book is a little weird. The other one was, called Pathfinders by Jim. Al-Khalili the growth of physics and astronomy in the Islamic world in their golden era, which was roughly coincided with dark ages in Europe. I really enjoyed the one too. there's a real, there's a really small book. , sorry, I ran really bad with titles of books. It's by George Gammon you know, The, he was a pretty famous, physicist.

Vikram

we have, we have notes for the show. You can always fill

Harish

yeah, I'll, I'll send you, I'll find out the name and I'll tell you what the premise of the book is. This character really likes going to popular science lectures. And so you go to this lecture and it'll keep listening to the lecture and then fall asleep and dream. And so if he's listening to a lecture on special relativity, then in his dream, he'll go to a world where, you know, the speed of light has been slowed down. Right. And so we just normal human speeds. You can start seeing relativistic effects and here's a wonderful description of what that world would look like, is really nice. I really enjoyed reading it.

Vikram

this is amazing.

Subu

that's nice. In the way of wrapping up this episode. Now every couple of years, right? Or even even more frequently than that, I run into this existential crisis, I come across say a, a graphic or a picture of the known observable universe. And then they sort of compare that to what humans think the scale of the universe actually is versus what we can observe. And I see pictures like that, which is tiny compared to how big the universe in reality could be. Then I, I read these theories where big bang could be just one such event, and there could easily have been many, many big bangs across all of the places. And then there's another singularity of theory or whatever would say is that if you look, if you could look before the big bang before the singularity, maybe it was a big crunch. It was a sequence of many big bangs leading to big crunch. And we are just in one such thing. Right. And so when I think of all this and I run into this existential crisis where I questioned the insignificance of one human or, all of our being in general. And the reason the existential crisis comes up is because I am, on a day-to-day basis. I'm so myopic, I am, I'm so worried about, okay. The, the meeting that is coming up or after meeting I'm really frustrated with something someone said at the meeting and I feel like I'm caught up in all these little things and at the end of the day, or end of the week, I sit back and I wonder, I mean, what is the point in all of this? What is the point in existence and what is really the meaning of life, right. And the reason I don't really come up with any good satisfactorily answered every, anytime I think about what the meaning of life is. And the reason I wanted to ask you this question specifically is because, I know that both of us take an interest in, in Vedic texts and ancient Indian literature and things like that. And. There are some stuff that the way that see, which is sort of comforting in a way, but that is what it is. They're not really answering the question of meaning of life, but more so, just so that you can take some comfort from it. So with that, take a, what, what have you done? Do you run into this kind of, for someone like you, who's looking at the universe all the time and wondering about this, do you ever run into a existential crisis?

Harish

I mean, I do, I don't know if it's a crisis for me. Like, I don't feel like it's a crisis. It just a really arresting thought . for me. But for me it's more to do with like, what should I do? Like, like in that, that is my flavor of existential crisis. And so it's more, yeah, what should I do? you know, should I just do research? Like, should I just be a little more hedonistic and like enjoy life? Should I just drop all of this and go and live with my folks in India? Because they are my kin, And nobody's going to love me as much as they will ever. And so, yeah, I think these are the kinds of questions. And of course you can extend that to a bigger scale and be like, you know, what should we do as humans? Like, why are we here? And I always come to the sense that I don't think there is a direct answer. And I don't think we should look to science for these answers because scientifically speaking life is meaningless in the sense that if you, I mean, to the extent we can tell the, you know, we can roughly know how the universe came into being, how everything happened. We know how life evolved. Like Darwin's theory seems very close to the truth, if not the absolute truth you know, how, how life evolved. And if you take that seriously, then you have the control that life is meaningless in the sense that there is no external meaning that can be given based on these physical processes. And so the meaning of life is whatever you think the meaning of life is, because your guess is as good as anybody else's, there's no external meaning given scientifically speaking. Right. And so, but it doesn't solve the problem because it's like, okay, what meaning should I give to life? Right. Right. And so it just shifted the focal point to yourself, which is a big step, but you're you know, you're still left with that question. I think what appeals to me is my view of this is colored by a Hindu philosophy because that's what I was exposed to. So I'm pretty, what appeals to me is the sequence of, ideas that Krishna gives to Arjuna in the Bhagawad Gita, right? you know, I don't, agree with everything or it doesn't like if everything that doesn't appeal to me, but the sequence really appeals to me. So he starts off by saying you are supposed to fight this war because this is your Dharma. Like, and it's a very cold logic. It just says that you've had a upbringing as a warrior. So your meaning of life is to just to do your duty as a warrior. You're supposed to just act, keep your emotions, everything to the side. And that works for some people, like a lot of people find meaning in just acting out whatever their Dharma is But it doesn't work for a lot of people. Arjuna is actually unconvinced by that. And you know, Krishna goes through the different stations and then he ends with, for me, the most distasteful, meaning of life, which is, I am the Supreme Lord. So I just said this, or you're supposed to do it. I'm the alpha and the omega and whatever. you know, he doesn't give him an injunction. He just says you know, just trust in me it's, as a scientist, that's obviously the most distasteful, but I think at different points in people's lives and that for different kinds of people, it's going to be a sliding scale between one or the other, and so some people are really into, kind of for devotional, meaning to life like, and so they find meaning in almost devotional things, kind of a very emotional attachment to ideas it could be for very good reasons. It could be to do charity, these are the more religious people I would say. And then there are people who are on the other extreme, which is they are just following their Dharma kind of thing. Like my Dharma, for example, is that of a professor. My . Meaning in life is to teach, is to do research to the best of my abilities, blah, blah, blah, blah, blah. And so the other that might have is that of a husband. and of a father and you know, like it's a more duty bound view of life. And I think what really helps me is based on the mood I'm in or based on the, the stage of life I am in under circumstances is to be flexible, to move between these two ends helps in solving some kind of an angst you might have about existential questions. I dunno. Does that make sense?

Subu

That is a good, that's a great answer.

Vikram

Good analysis. I like that one.

Subu

yeah, that is a great, that's a good answer. Okay. So on that note, I think we are very fortunate to have a grownup with you. I mean, all of us being friends from childhood, I think that's definitely something special making a friend during childhood and then sort of growing up with them. And now we are pushing 40 and it's good for us to collectively look back and see how life has been and where we're going. So, thanks for spending two hours of your time with us. This is great. I think we definitely will have to have you back on the show and for updates and astronomy and stuff in life and stuff like that. So that's it. Thank you very much.

Harish

well, thank you guys. It was a lot of fun as always. I mean, chatting with you guys has been, as much fun as it is today from day one.

Subu

That's all for this episode. Thanks for tuning into half-life show. This week, you can find us on iTunes and Spotify and everywhere else that you typically get your podcasts. If you have a question, you can reach us on Instagram. Our handle is at half-life dot show. And if you would like to see a transcript of this episode, you can find it on www dot half-life dot show. All right, until next time.

14: Dr. Harish Vedantham: A Journey to the Stars