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Dr. Thomas White: I love working with undergraduate students. They are so enthusiastic and excited to be in the lab. Sometimes after working in a field for a decade, you get a bit jaded and I forget that I'm blowing stuff up with lasers, like this is very exciting research. The undergraduate students never forget this. They're always sort of aware that we're doing something really exciting.

President Brian Sandoval: This is Sagebrushers, the podcast of the �Ƽ��Ӱ�ԭ��. Welcome back Wolf Pack family. I'm your host University President Brian Sandoval. Imagine researching space, not by looking at the sky, but by creating mini planets and stars in a lab. Today's guest has done just that, using some of the world's largest lasers. Dr. Thomas White, an associate professor in the Department of Physics in the College of Science joins me now to discuss his fascinating research, its implications for the science community and humanity as a whole, his passion for mentoring students and more. So, let's get started.

Dr. White joined the university in 2017 from the University of Oxford where he earned his PhD among his many accolades. Dr. White was awarded a Mousel-Feltner Excellence and Research award in 2021, won a National Science Foundation early career award in 2021 and earned the Clemons-Magee Professorship in Physics in 2022. His area of research is laboratory astrophysics where he focuses on the behavior of stars and planets, not by gazing through telescopes, but by recreating the astrophysical conditions in the laboratory, effectively creating mini planets and stars in a lab. This is going to be such a great conversation. So, today's podcast is being recorded at the Reynolds School of Journalism on our University's campus. Dr. White, welcome to Sagebrushers. I'm excited to share with our listeners some of the fascinating research you're conducting here on campus.

Dr. Thomas White: Thank you for having me.

President Brian Sandoval: So let's dive right into this and there's so many things to talk about, but first into the fascinating realm of studying space using lasers. So, could you share insights into laboratory astrophysics and discuss its potential implications for our understanding of planetary and space science?

Dr. Thomas White: Absolutely. We all love talking about space, black holes, exoplanets, molecular clouds, and supernova explosions. These are all things that really excite physicists like me and the public. But, one of the difficulties with researching space, and this is going to sound a little obvious, but space is really big. All these things are super far away and hard to study, and of course we have really telescopes now and the James Webb telescope that just went up. If you haven't found a new background for your computer, you should Google some of the NASA images from the James Webb Space Telescope. What it doesn't tell us is anything about what's going on inside these things. So, inside the planets, inside the stars, and of course we have satellites which we can send up which might measure something about the planets in our solar system and maybe even send a rover to Mars.

We know very little about the insider planets and we know even less about planets outside our solar system, so-called exoplanets, we just don't know anything. Even simple questions like “Is the interior of the planet a solid or a liquid?” We don't know the answer to many of those questions. This is important if you want to discover, for example, an earth-like planet, if you're looking for a planet that can support life. So, my research involves trying to recreate those planetary conditions here on Earth instead of studying them through a telescope, because if you can recreate them on Earth, it's much easier to diagnose them and see how they are behaving. So, the way that I like to do that is to use very, very big lasers to heat and compress material down to recreate those extreme states that we find inside planets and stars. So, essentially laboratory astrophysics is creating mini planets and stars in the laboratory that we can then study.

President Brian Sandoval: Which is incredible. So, your work involves using some of the largest lasers on the planet, some over three football fields long, and worth billions of dollars. What's it like working with these colossal types of equipment? How do they aid in your research endeavors?

Dr. Thomas White: It is a fantastic opportunity and a real pleasure to use some of these billion-dollar, and that's billion with a B, machines. And like you just said, they're as big as three football fields. So, these enormous machines, when they fire these lasers, they actually put out more power than the entire rest of the planet combined, but they're only on for a few nanoseconds. So, they're not using a ton of energy, but they're more powerful than the entire rest of the planet combined. I'm going to explain how we recreate the planets now, and I'm just going to use two pieces of high school level physics. The first is what? The lasers are all fired at the outside of our target, and all that energy gets absorbed and it gets really hot. And so, the first piece of physics you need to know is that hot things expand. So, the outside of my target expands, it essentially explodes. And then the second piece of physics is Newton's third law. That's the one that says for every action there's an equal and opposite reaction. So, when the outside explodes, the inside implodes essentially crushing down to create extremely high densities, the kind of thing that you would find inside these planets, and so that's the way in which we can use lasers to recreate these extreme states. The issue of course is that it doesn't last very long. So, if you think of the center of, for example, Jupiter, it's surrounded by the whole rest of Jupiter holding it together. But, if I create a mini part of Jupiter in the lab, it's surrounded by nothing. And so, it explodes normally in about 10 nanoseconds, which is 10 billionths of a second. So, when I want to take my measurement and our favorite measurement is to just x-ray this planet, just like you get an X-ray at the dentist, we take an X-ray of our planet. We have to have a very short pulse of X-rays that comes within those 10 nanoseconds before it explodes. For that we use another billion dollars laser, which is a three-kilometer long X-ray laser in Stanford, California. This is the brightest X-ray source on the planet. We use this laser, this three -kilometer long laser to X-ray our planet to try and discover what's going on inside the center.

President Brian Sandoval: So, another question. You called them exoplanets, correct? That are outside our solar system. How do you select an exoplanet that you would like to recreate. 

Dr. Thomas White: Well, we have discovered an enormous number of exoplanets right now. And so, they're discovering them every day. The Kepler space telescope discovered many of them, but we really only know two things about exoplanets. One is we know how heavy they are because they make the star that they orbit wobble around. So, if you look at that wobble of the star, you know how heavy the planet must be. The second thing we normally know is how wide the planet is, the radius of the planet, because when it goes in front of the star, the light from the star dims. So, when we're searching for planets, we're just searching for planets that really are earth-like in their mass and their size and the distance from that star that they're orbiting. We don't really know what even the material is inside these planets. So, right now it's almost a complete guess on that front.

President Brian Sandoval: Do you think there's an Earth-like planet out there?

Dr. Thomas White: Oh, for sure. For sure. There's an Earth-like planet out there. I don't know if any of the ones that we've seen yet are exactly earth-like, but there's definitely an earth-like planet out there.

President Brian Sandoval: Well, that's exciting. So, this is all amazing, so, could you give us a glimpse into your current and upcoming projects? And what exciting developments or discoveries can we expect from your research?

Dr. Thomas White: Absolutely, I can. I will just talk briefly about some work we just completed and put online. So, you can go read it on the archive if you want to. But, we were interested in looking at how sound waves travel through the center of planets. So, we did an experiment looking at sound waves inside the ice giants of our solar system. So, this is Neptune and Uranus, and of course, we can't shout into the planet like “hello,” and then wait for the echo or anything. So, we actually use the X-rays to visualize the sound waves inside the material. So, in the X-ray images, you can see the sound waves in the material and work out how fast that's going and is important for understanding how quakes, and it's not called earthquakes if it's in a different planet. So, this is kind of a fun …

President Brian Sandoval: Uranus quake.

Dr. Thomas White: Yeah, and so we can actually work out how fast those quakes might travel through the center of the planet. And so, we did some experiments like this at that three-kilometer-long x-ray laser that I talked about, and we were able to measure those sound waves inside this extremely dense material for the very first time.

President Brian Sandoval: So, what constituencies are most interested in the research that you produce?

Dr. Thomas White: A wide number of people are interested in the research that we do. Mostly, what we try to do is to benchmark or validate models that astrophysicists are using. So, they use these quite often phenomenological models, those kind of simplified models of how important properties might change with density and temperature. And we are able to benchmark those models against real experimental data. Most of the time it's wrong, which is great for us, not so great for the astrophysicists, but really good. When we find something that's wrong, we celebrate in our lab because we really have a great opportunity to correct something. In some of the most famous cases, the laboratory astrophysicists have sent the astrophysicists back to the drawing board to think about how the interior of these planets or the opacity of the sun, for example, has to be recalculated.

President Brian Sandoval: So, you certainly are busy. Switching gears a bit, in 2022, the U.S. achieved controlled nuclear fusion using the largest laser in the world, which you have used, and made headlines globally. Why is this achievement such a pivotal breakthrough not just for the scientific community, but for humanity as a whole?

Dr. Thomas white: Yeah, I'm so glad you asked about this. It is probably the biggest achievement in my field of research, which is to achieved controlled nuclear fusion on earth. So fusion, if you don't know, is the process in the sun by which lighter elements like hydrogen and helium are fused together to create heavier elements, and in the process release an enormous amount of energy. And so, it's the process that powers the sun. We've been trying on earth to recreate this process for almost a hundred years now. And if we succeed, then we've essentially got an unlimited clean energy source that we could use the hydrogen from sea water to power it, and we would've sort of solved one of humanity's greatest problems, but it's not an easy problem. And, after one hundred years of trying, we finally got it to work in December of 2022 at the Lawrence Livermore National Laboratory, and they were able to get three megajoules of energy out of a system and put in just two megajoules of laser energy. So, they were able to create energy from nothing essentially. And so, they did this in December 22. Since then, they've improved it even more. They're now repeating this and having much more success. And, even though they're a long way from a power plant, it really has sort of ignited a sort of renaissance of research in this area. And, there's a huge amount of private and federal funding going into this research. Enormous number of startup companies now looking at fusion. And so, I would say that if you're a young scientist and you don't know which area of science to go in, this is an area which is just starting to see a big influx of money and ideas. So, it's an exciting place to be.

President Brian Sandoval: So, a moment ago you talked about nanoseconds. What's a megajoule of energy?

Dr. Thomas White: A megajoule is a million joules of energy. So, it's not a ton of energy actually. And so, if you wanted to get this into a power plant, and that's really the next goal is to turn this into a power plant, you need to do this sort of once a second. So, every second you do this experiment. Right now we're doing it about four or five times a year. So, you can see there's a huge technological hurdle to get it into a power plant, but at least the science behind it has now been proven.

President Brian Sandoval: But, someday.

Dr. Thomas White: Someday, someday, there is this joke that fusion is always 50 years away, but maybe it's true now. Maybe today is the day that that is actually true.

President Brian Sandoval: So, bringing it back closer to home, your dedication to fostering curiosity and creativity in students earned you the Clemons Magee Professorship. So, could you share your experiences of working with students in your lab and what notable accomplishments have they achieved under your mentorship. 

Dr. Thomas White: I love working with undergraduate students. They are so enthusiastic and excited to be in the lab, and sometimes after working in a field for a decade, you get a bit jaded, and I forget that I'm blowing stuff up with lasers. Like, this is very exciting research. The undergraduate students, they never forget this. They're always sort of aware that we're doing something really exciting. And I've been super lucky to have funding from the NSF and the NNSA and Susan Clemons and Gary Magee for their support towards funding undergraduate research at UNR. And I've had so many great students, just a couple, Jacob Molina, he won the Gold Water scholarship when he was here. He's now at Princeton studying physics. Landon Morrison, he's now in Oxford studying physics. I'm incredibly jealous of him and many others who've won many awards while they were here. Last semester, it's not all physics, Two of my favorite people, Jaya and Jason, they did an outreach event at the Discovery Science Museum during the partial solar eclipse, and they presented some of our work to the public, and they had these little coloring books, space theme, coloring books for the children and just put on an amazing event. I'm constantly blown away by how good our undergraduates are here at UNR. I really love the fact that there are all these programs here, the McNair program, the NURA, the Prep program run by wonderful people like Tanya, Heather and Carla before them to support paid undergraduate research positions because many of our students can't participate in research if it's not paid, so, all of these opportunities, it's something that we do very, very well here.

President Brian Sandoval: Well, thank you. Gary and Susan, are friends and I'm so grateful for their support of the University. So, I'm sure our listeners are wondering, you moved over 5,000 miles from the UK to Nevada, and that must've been quite a transition. So, what was the move like and what motivated your decision to join the University of Nevada?

Dr. Thomas White: Yeah, it was a big move. I hadn't even thought about moving to America. It was not on my radar. Reno certainly was not on my radar, but a position came up, and the physics department here is pretty well-known for what I do. There are some amazing professors here, and that sort of motivated me to apply. So, I applied and the interview process for a professor is quite involved. There are many, many stages. I remember getting to the third stage of the interview and I was flown out here for the in-person interview, and I remember I was put into the Silver Legacy Casino the night before my interview chosen by UNR, I should add. I'd never been in a casino before. I was jet-lagged walking around the casino at about 2 a.m. thinking what is going on? But, then I interviewed and I got the job, and it took a while to get used to living here. The West Coast of America is quite alien. It's kind of weird. I think I have a lot of empathy with our international students and faculty who move a long way. It does take some getting used to, but once you get used to it and you start getting into, well, all of the outdoor activities and things like that, so the skiing, and the hiking, and the camping and I got a dog now. I wouldn't want to live anywhere else. This is such an amazing place to be, and I think it's the worst kept secret that Reno is such an amazing place to live and everyone should want to move here if they can.

President Brian Sandoval: Well, unfortunately we're out of time, but I agree with you that it's an amazing University. It's an amazing community. It's an amazing region with the Sierras and Lake Tahoe, and we're very blessed to be able to live here. So again, that is all the time we have for this episode of Sagebrushers. Thank you so much for joining us today, Dr. White. We learned so much and thank you for your contributions to the University and our students. Ladies and gentlemen, join us next time, for another episode of Sagebrushers as we continue to tell the stories that make our university special and unique. Until then, I'm University President Brian Sandoval, and go pack.