Detecting gravitational waves with Jonathan Cripe
The Laser Interferometer Gravitational-Wave Observatory, LIGO, lab detected the first gravitational wave on September 14, 2015, and there has been
a flood of detections ever since. How is it possible to discover cosmic marvels such
as gravitational waves and black holes? Jonathan Cripe, a graduate student in the
Department of Physics and Astronomy, provides insight into this question by sharing his experience working with LIGO
and his involvement in developing the next generation of black hole detectors. (Transcript below.)
Listen to the full episode below, and subscribe to LSU Experimental on Apple Podcasts, Google Play, Stitcher, Spotify, TuneIn or anywhere you get your podcasts.
LSU Experimental is a podcast series that shares the research and the “behind the scenes” stories of LSU faculty, student, and alumni investigators across the disciplines. Listen and learn about the exciting topics of study and the individuals posing the questions. Each episode is recorded and produced in CxC Studio 151 on the campus of Louisiana State University, and is supported by LSU Communication across the Curriculum and LSU College of Science. LSU Experimental is hosted by Dr. Becky Carmichael and edited by Kyle Sirovy.
Transcript
Becky Carmichael
[0:00] This is Experimental, where we explore exciting research occurring at Louisiana State University and learn about the individuals posing the questions. I'm Becky Carmichael and today Jonathan Cripe, a graduate student in the Department of Astronomy and Physics shares his involvement with LIGO, and how he works on the development of the next generation of black hole detectors.
Jonathan Cripe
[0:24] I'm sure you heard about the recent discovery of gravitational waves, either in the news or through social media. But did you know that one of the detectors used to catch these waves as it passed through Earth is located right here in Livingston, Louisiana, only about a 45 minute drive from LSU? And did you know that there's research being done right here at Louisiana State University to help us detect even more gravitational waves in the future. 100 years ago, Albert Einstein published his theory of general relativity. Einstein's theory completely redefined our understanding of the force of gravity and how mass such as our planet, the sun, and all the stars in the universe, interact in space and time. Many parts of Einstein's theory have been tested and proven correct. The theory correctly predicts the orbit of Mercury around the sun and allows scientists to correctly calculate the orbit of GPS satellites, so that we can all use our GPS devices in our cell phones and cars. One part, the prediction of gravitational waves, has never been directly confirmed though. The discovery of gravitational waves by LIGO which is also known as the Laser Interferometer gravitational wave observatory on September 14 2015, is a big deal because it proves that part of Albert Einstein's theory. It is also important because it opens a new window to the universe. For the first time, we're able to see black holes and observe the violent effects caused by two black holes colliding together. The collision that LIGO recently detected last year on September 14, 2015, was so violent that in a split second, the collision released more energy than the energy released from all the stars and the universe combined. Pretty cool, huh? Before LIGO, we were deaf to the sounds of the universe. Now, for the first time, we're able to tune in to the sounds of the cosmic symphony. I work in the quantum optics lab with Thomas Corbitt, here at LSU. In the lab, we study radiation pressure noise, which is a type of quantum noise or uncertainty that limits how well the LIGO detectors work. To get an idea of what radiation pressure noise is; imagine that you are in your backyard and spraying a swing with a jet of water from a hose. What happens when the water hits the swing? It pushes it back. But if you zoom in, so that you can see the individual droplets of water hitting the swing, you might notice something. Since the water comes in these individual drops, there are times when no water is hitting the swing. When this happens, the swing begins to fall. But then another drop of water comes and pushes the swing back again. So on this small scale, the swing is moving back and forth all the time. This is radiation pressure noise. In our lab, we replaced the water hose with a laser and the swing with tiny mirrors. The individual water drops are single particles of light called photons. By studying radiation pressure noise, we hope to find a way to make it smaller and get rid of it all together. If we're able to do this, we can apply what we learn to the LIGO detectors to make them even more sensitive and able to hear more gravitational waves. These upgrades will allow LIGO to turn this into something like this.
Mark DiTusa
[3:37] We're here in the KLSU Studio talking to Jonathan Cripe. So ah john, what do you do?
Jonathan Cripe
Well, I'm a graduate student here at LSU, in the physics department working on my Ph.D. And I'm part of the LIGO collaboration. And specifically what I do is I work with Dr. Thomas Corbett on trying to reduce the quantum noise as a part of LIGO
Mark DiTusa
I see. So how often do you go out to LIGO and basically, do you work directly at LIGO? And how often are you at LSU.
Jonathan Cripe
So our lab is actually on campus and the basement of Nicholson Hall. So most of my work is done there on campus. But I do occasionally go out to the LIGO site and Livingston for meetings or special occasions. But most of the time I spend on campus.
Mark DiTusa
Okay, so how did you? I mean, did this can be either how'd you get into the specific kind of physics that you're doing? Or how'd you even get into physics in the first place?
Jonathan Cripe
Well, I first got into physics, back in high school. I took a high school physics class, and also AP Physics, and I was really interested in it then. So when I was applying to colleges for undergraduate, I thought, well maybe I want to go into physics as a major. And so that's what I did. I went to DePaul University, where I majored in both math and physics. And how I specifically got into LIGO and gravitational waves; I think it was either my sophomore or junior year, I was taking a class where we had to write a research paper, and I decided to write that paper on how do we know black holes are out there? You know, is there any evidence that we can use to prove that black holes exist? And when I was doing the research, for that paper, I came across some articles and some things in magazines about something called LIGO that which I'd never heard about and what you know, what gravitational waves were and what when they would be detected. And so that was when I first sort of learned about LIGO. And I had a lot of fun writing the paper. And after that, going into my senior year, I thought well maybe I'm going to go to graduate school, what's something that I'm interested in? And the answer for me was, I'm interested in gravitational waves and joining LIGO. So then I applied to LSU for graduate school. But before I came here, I actually took a year break, and went to Germany and worked at the Albert Einstein Institute doing both research and taking classes. And that's an institute that just focuses on gravitational waves. So it was a great experience. And then I came back here to LSU and started my PhD. And here I am.
Mark DiTusa
So. So what was the process of deciding; okay, I'm going to take a year to go to the Albert Einstein Institute? And, basically, so did you get into LSU and then go; oh, I'm going to take a gap here? And then also tell us like how it was living in Germany also.
Jonathan Cripe
Yeah, actually, I applied for several scholarships and fellowships. And one of them was to the German government called the DAD or dad scholarship. And it's sort of like the US version of the Fulbright where they have money for students and also professors and other researchers, to have an exchange for either a year whole masters or PhD program that you can do. And so I applied to that my senior year and actually found out that I got the fellowship while I was visiting LSU after I'd been accepted. Wow. So I talked with the people here and said, well, this opportunity came up, can I do this and then come back to LSU a year later? And they said, oh, yeah, sure. That's, that's a great opportunity. Go do that. and, you know, we'll see you in a year, hopefully. So I had a blast, like I said, in terms of work and, you know, learning about gravitational waves is a perfect place to be. There were classes that were very specific to what I want to do, which then when I got back to LSU, sort of transferred in his credit. But also, it was a lot of fun living in Europe for a year, getting to travel around on the weekends. See a whole bunch of cool places. And, yeah, there's a lot of fun.
Mark DiTusa
I've heard so many good things about traveling abroad and getting to experience even a different continent, you know? And so I guess, how much do you, how much stock do you put in that? Did you feel like you gained a lot by going to a different continent and kind of getting a different way of life for a year? Or would you encourage college students to study abroad if they could?
Jonathan Cripe
Yeah, I definitely encourage people to study abroad if they can. I think it's really an eye opening experience to be able to go and meet different people. See how different people live. See how similar and different people are around the world. There are people just like we are, they just, you know, may do things a little bit differently. But I was very fortunate to be able to have that opportunity. If I could go back, I definitely do it again. And I think it will pay off in the future just for all the connections that I've made while I was there. Now I get to go to, you know, conferences and see old colleagues that I met, you know, over the years, and I think that'll, you know, really pay off in the future.
Mark DiTusa
Yeah, that does make sense. Um, kind of returning to a completely different, not completely different, but different ideas. So if you could tell your younger self one thing whether this has to do with, you know, getting into physics and studying science, or whether this has to do with I don't know anything that maybe there's something very specific that you want to talk about that it isn't necessarily science, like what is that one thing you tell your younger self to do?
Jonathan Cripe
Um, I guess I'd tell myself to, you know, always have fun and enjoy what you're doing. I think that's really important. Luckily enough, here at LSU I really enjoy the work that I'm doing and all the people that I know and work with and have friends. But I think that's really important thing to keep in mind is, you know, if you're not having fun doing what you're doing, maybe you should try doing something else.
Mark DiTusa
That makes sense. I mean, they're two different lines of thought, I think. Or maybe it's like a kind of a line, you can either have fun in your job and and really enjoy what you're doing and maybe the goal isn't necessarily making as much money. Or you can be on the other opposite side of the scale, which is you do something that you feel like makes a lot of money, but isn't necessarily your hobby as well, right? And so and if you can manage to somehow combine really enjoying it and making lots of money, that's great, but it's really hard to do. And so I totally subscribe to the, I mean, yes, you want to make money and be able to live, but I mean, I'm going into physics and it isn't unnecessarily the most lucrative, but it isn't, I'm going to have to say this in a way that isn't necessarily bad. It isn't the most lucrative thing to do. Like I could go into chemical engineering and go into industry and that's definitely like, if you look at the salaries that these people make, even right out of college, it's it's really good. But I don't know. I really, I really want to do something that I enjoy. Right? And I also subscribe to that idea. So after graduate school, do you see yourself becoming professor? Or do you do you want to go into industry? Or, you know, what do you see yourself doing?
Jonathan Cripe
Yeah, that's sort of something that I've been starting to think more about. Over the past few years, it's always been something that's, you know, three, four years in the future, I don't really have to think about that right now. But now I'm roughly a year or so away from graduation, so it's a lot bigger deal that I have to think about it. And every time I go home or visit friends or family, they're always asking, well what are you going to do next? I've been thinking about it, I don't have one thing that I have to do, right when I graduate. There's lots of things that I'd be interested in doing. I really do enjoy teaching and sort of the academic aspect and also doing research, so I think getting a job as a professor would be very nice. But I'm also open to maybe working in industry. Whether it be you know, for a private company doing some sorts of research and development for product they're making, or sort of more long term research about something that they're trying to push the frontier on, you know. But I don't have a solid answer for, you know, what I'm going to do next.
Mark DiTusa
I mean, that's fine. I mean, you one your a year out, but like they are really a lot of opportunities, and something that people don't realize, even just an undergraduate is getting a stem degree really makes you attractive to things that are outside of STEM. I know people in physics who ended up going to law school, who end up going to medical school, who ended up doing something completely different. Like, if you go to the society of physics students web page, the people who ended up ended up being an Imagineer for Disney. Like, there's just the stem discipline prepares you by way of thinking.
Jonathan Cripe
[12:50] Yeah, I agree.
Mark DiTusa
[12:51] I mean, if, if you end up not doing physics, I feel that or if you end up not doing stem discipline in for your job, that way you think you really makes you more attractive? And I think.
Jonathan Cripe
[13:03] Yeah, I think for, you know, most jobs out there, it's going to involve some sort of critical thinking or problem solving, which, you know, as STEM students we're trained very well at. So those, those really transfer over.
Mark DiTusa
[13:16] Yeah. What did you see yourself doing as a kid? And did you see yourself going into into science? Or do you see yourself doing something different? Or did you not have a goal at all? You know, I don't know.
Jonathan Cripe
[13:28] I think well, when I was really young, the thing that I wanted to be when I grew up was to be like a baseball player. Or, you know, a superstar in some kind of sports. That didn't really pan out. But I was always interested in sort of learning in general, but also math and science. Just sort of learning how the world works or how things in our life work. So I think maybe that's, you know, part of why I decided to do science and physics, specifically is, you know, we're studying things and trying to figure out why, you know, why, why, why I always my mom always says that, you know, that was my favorite word when I was growing up, you know? Why mom? Just cuz. Well, why? So, I think it's, you know, I've always been interested in learning about different things.
Mark DiTusa
[14:25] I understand. Yeah. And science is very much a way to kind of try, especially physics you drive, really, the fundamentals of, of why things are, and that's what really appeals to me. So, so what about gravitational waves, or what you're doing at LSU, what do you enjoy so much about it then?
Jonathan Cripe
Well, one of the things I really enjoy about LIGO, in general, is just the diversity of the people and also the work that we do. Since it's a worldwide collaboration, I get to meet people that come to Louisiana from all over the world. Or when I go to conferences I get to meet people from all over the world. And everybody has a different way of thinking about something or approaching a problem. So that's really fun to be able to just get all those different inputs from different people. And then sort of going from that, you know, you make friends as you go through life. And then a lot of these people that, you know, you get to meet a lot of really neat people, as part of LIGO.
Mark DiTusa
For LIGO. And for your research at LSU, why are you attracted to this specific thing that you do day to day?
Jonathan Cripe
[15:37] Well, I'm definitely more on the Experimental aside. I like building things and it, you know, it gives me a real sense of accomplishment when you can, you know, start from nothing, and then build your own project. I think the work that LIGO does is is just very interesting, because we're really looking at the universe in a completely new way. One way that I sort of like to think about it is, you know, hundreds of years ago, Galileo built the first telescope and before that, you know, people looked up in the stars, and they just saw little twinkling spots. But then after the telescope, we're able to tell, well, this is that type of star, or this is a planet or, you know, and we're able to categorize and sort of, you know, learn about different things. Well, now LIGO is able to sort of look at things in a different way, or listen to the universe, which we were never able to do before. So it's really a something that's brand new. It's pushing a lot of different technologies to be able to do this. So I think it's really cool that, like I said, the work that's being done in LIGO is very diverse. So there are people that are very good experts on lasers. There are people that are experts on mirrors or different type of optics. There are people that are experts on vacuum systems. And you know, the list can go on and on and on. But there's, there's so much work that's being done that you just sort of have to choose what sounds interesting, and there'll be something for you to do.
Mark DiTusa
[17:08] I guess kind of, I think the question that everyone would want to ask you is how did it feel to kind of get, I don't know whether you knew that the announcement of gravitational waves was going to happen when it did? I think you probably did. How did they feel it kind of like finally be validated? Like, yes, everything that we've been working upon for, you know, X number of years has been like, we have been validated and everyone was talking about it. How did it feel like what was it, what was it like kind of living in that moment?
Jonathan Cripe
Yeah. So I actually did know, the morning of when the gravitational wave event actually happened back on September 14. There was a thread of emails that went around that morning, where people were saying, well is this real, you know, what is this that we're seeing? And over the next couple of weeks or months, people sort of went through a checklist of different things they had to check or look into to, to make sure it was something real and not something from the outside. And so that was really interesting to be a part of that and just sort of see how the process works. But it was also really hard not being able to tell anybody, because we were all sworn to secrecy. We couldn't go out and, you know, tell anybody for fear that they would go and tell the media and then, you know, something would be leaked. Because our fear was, if this is something that's not real we don't want it to get out and then have to cover it up.
Mark DiTusa
Yeah.
Jonathan Cripe
[18:33] So it was a lot of fun when last February 11, which is actually a day after my birthday, so that was also kind of, we got to reveal that, you know, this is the big secret that we kept. And to be able to share it with the world. And like you said, it was it was amazing just seeing how interested people were. It made national and international news. It was all over, you know, Facebook, Twitter. People were still interested just walking around here on campus or in Baton Rouge. Friends that, you know, might not have known what I did before, sort of were interested in what I was doing. So they would ask me lots of questions like, oh, well, why does it do this? Or, you know, how do you know this? And so that was a lot of fun, just to be able to explain, you know, what I was doing and what I was a part of to, you know, friends and family. You know, I wasn't just the crazy scientist anymore. It was something that was, you know, real and we were doing something special. And that's continued even, you know, what is it now about six months after we first made our announcement. When I went home for Fourth of July aunts and uncles were, you know, asking me about it. And also I got to, in the spring, go back to my undergraduate at DePaul and give a couple talks to the physics department there. So it's just been, I guess, a lot of fun being able to share what I'm doing and what we're doing as a group with the world.
Mark DiTusa
[20:01] That's awesome. Is there anything else you wanted to talk about?
Jonathan Cripe
[20:05] We're really excited that we are able to, for the first time detect gravitational waves. But we're not done yet. We're not going to stop. We're going to keep making our detectors even better in the hopes that we can detect more and more and more gravitational waves to continue learning about the universe.
Mark DiTusa
[20:22] And that's exciting. And, and this, this science it didn't stop in saying, oh, gravitational waves exist. Because the whole idea is that these gravitational waves well, like you said, kind of illuminate and allow us to see the universe in a completely new way, and that's really exciting. And this science is ongoing, I guess is what we're getting at.
Jonathan Cripe
[20:40] Yeah.
Mark DiTusa
[20:41] So hopefully someday in the future, if you if you stick with gravitational waves, maybe we'll have you back on some kind of check back in. You never know.
Jonathan Cripe
[20:48] Yeah, that'd be great.
Mark DiTusa
[20:49] Alright, but until then, it's been great. Thank you, john.
Jonathan Cripe
[20:52] Thank you.
Becky Carmichael
[20:55] Experimental was recorded and produced in the KLSU Studios here on the campus of the Louisiana State University and is supported by LSU's communication across the curriculum and the College of Science. Today's interview was conducted by Mark DiTusa and edited by Bailey Wilder. To learn more about today's episode, subscribe to the podcast, ask questions, and recommend future investigators visit cxc.lsu.edu/Experimental.