American Physical Society April Meeting
April 14, 2018
Columbus, OhioMeeting host: By:
Morgan Waddy, Matt Walker, and Levi ShultSPS Chapter:
Hello! Our names are Morgan Waddy, Matt Walker, and Levi Schult and we are the reporters for the Society of Physics Students from the University of Virginia. We had the pleasure of attending the April American Physical Society meeting and learning about the cutting-edge research that is happening right now. We got to meet lots of professional scientists, professors, postdocs, and graduate students, and talk them about their research and what’s is like to have a career in physics. Morgan and Levi were part of an undergraduate research group that worked to create timing solutions for pulsars while Matt’s research is in Condensed Matter Theory, studying topological phases of matter. In particular Matt has been working on a research project studying topological channels in bilayer graphene. Our group visited the April American Physical Society Meeting for three days and we also have three interviewers, so our report is split into three sections in addition to our introduction so each section has been written by a different reporter. Also, most of our interviews were audio-recorded, so to listen the full-length of our conversations you can click the annotations at the end of the report.
My name is Morgan Waddy, and I’m a first-year at the University of Virginia, and this is our Saturday from my perspective. On Saturday, we set out in high spirits to try and get the most out of our conference experience. We arrived in Columbus, Ohio late Friday evening, so our adventure got off to a bit of a late start, but our first order of business was going to Future of Physics Days: Lunch with the Grads panel. There we learned about several interesting facets of the graduate student experience. One thing that I learned was just how important REUs and other undergraduate research are to being accepted into a graduate degree program. During the panel we met a friend of one of our group members and decided to interview her.
Her name is Katie Chamberlain and she was a fifth-year undergraduate student at Montana State University and she regaled us with stories about her research as well as her personal life. She talked to us about her research in gravitational wave form modeling of black hole binary systems that received a “kick” during their creation and her plans for the future. She has worked with one advisor for most of her career and has done research on the constraints of modified theories of gravity in addition to her work with black hole binary systems. Even though she has done research revolving around gravity for most of her undergraduate career, she plans to branch out into high red-shift galaxy simulation in graduate school at the University of Arizona.
“I want to do something that combines theory and some other form of research. So, either theory and simulations or theory and observations. I don’t want to be a pen and paper kind of person for the rest of my life.”
After this interview, we interviewed the man behind the first panel we attended (and the man behind SPS), Brad Conrad.
He engaged us in a conversation about what SPS means to him and how he wants SPS to affect the undergraduate experience of students across the country.
“SPS is whatever it needs to be. Whatever you think it is, it is.”
In short, he wants SPS to cater to the needs of the undergraduates. Thus, he believes SPS’s should be designed by the undergraduates. One thing my fellow interviewer and I both connected with was Brad’s experience as an undergrad with “imposter syndrome”, which is the idea that although you’ve gotten to your position through your own merit you think that you are somehow tricking the people around you into believing your competence. Often as a physics student you may compare yourself to your classmates and conclude that they’re all doing better than you are and believe that you aren’t qualified to become a physicist, but this isn’t a healthy activity nor is it an accurate viewpoint. This point is especially important during the first year of college as everyone comes into university on a different footing. As Brad puts it, we shouldn’t entertain these self-defeating thoughts because physics isn’t easy for anyone and you don’t have to have it all figured out today.
After this encouraging conversation with the director of SPS and Sigma Pi Sigma we went on to view some talks. We originally planned to see the talk on the Third Generation of Gravitational Wave Detectors, but we mistakenly slipped into a talk on the recent Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo results, which was very interesting until the fire alarm sounded and we had to evacuate. After the evacuation, we viewed the actual Third Generation of Gravitational Wave Detectors talk and learned about the Einstein Telescope, the Cosmic Explorer, and SOGRO, then we met Matthew Evans, a professor of Physics at MIT. He chatted with us about how he nonchalantly chose his career path, his outreach plans for Cosmic Explorer, and his advice to undergraduates. A surprising fact about Professor Evans is his nonnormative approach to his education choices. As an undergraduate, he didn’t really give much thought to his major. In choosing to attend Caltech for graduate school, the most important factor in his decision was that Caltech had a nice campus. Fortunately he ended up finding a project he loved which was LIGO.
“I wanted to understand everything by the time I got old, and to do that I should start with physics”
It was quite refreshing to see that Matthew Evans’ story was like a lot of kids’ story in the way that he didn’t have it all figured out yet. He doesn’t recommend his path to undergraduates though and, and he thinks that it’s ideal to plan your future out. But he emphasizes that even though it is likely your plans may fail, you will end up just fine in the end.
After this conversation some members of my group ran into Anne Archibald, a researcher who works at the Netherlands Institute for Radio Astronomy (ASTRON), and we decided to interview her. Anne Archibald gave a plenary talk that weekend on her recent work studying an extreme triple system that has been observed using pulsar timing. She talked to us about her evolution from being a mathematician, trained as a number theorist, to a pulsar astronomer among several other things. After she received her master’s in number theory, Anne went to McGill and originally became interested in pulsars through a friend who was working under her PhD supervisor Vicky Kaspi as well. Her friend was looking for pulsations in X-ray binaries and had tried several techniques, but Anne suggested a better one. They ended up successfully implementing this technique. Following that experience she realized that while being a mathematician is great; when you’re a scientist you can see if the ideas you have line up against the natural world.
“In mathematics you come up with a clever idea, you write it up, you put QED on the end, and you publish and you hope you weren’t wrong. You can be confident, a proof is a proof, but that’s all that happens. In astronomy – in pulsar astronomy – you have a clever idea, you write the code, you run it over real data, and you find the pulsar, or you find the timing solution that lines up all the pulse arrival times. You take your clever idea and you bang it against nature, and if it was clever enough you find something new”
The reason why I decided to study physics was because I was interested in the natural world, and I thought it would be best to stop wondering and start learning so that someday I too could see if my ideas lined up with the truth of the natural world! Anne’s first point truly resonated with me, but she also went more in-depth about her belief in cross-pollination between disciplines. That’s how she got started in the field of pulsar astronomy, and throughout her career she’s seen that this diversification of ideas has helped to bring lots of new and different things to the table. That’s why she finds conferences like this to be frustrating because it’s tempting to only go to talks that pertain to your topic rather than broadening your horizons by sampling other ideas.
After this insightful talk we were happy to find that there was food being served at the Welcome Reception which gave us some time to decompress after such a busy day. We were all quite excited to be able to hear Rainer Weiss in person, and we all hoped that we could possibly interview him. His talk revolved around his Nobel-Prize winning development of LIGO, but there was also a Q&A session that was very illuminating. One recurring theme among questions asked was, “when was a time you thought you might quit?” I thought his answer was very nonchalant, but truly telling – he said he never really thought of giving up because even though there were various problems popping up every day and the work seemed to not be progressing the way his team had hoped, he continued on because he loved his work. Even though there was a different problem that had to be solved every day, the problems were interesting and he knew that solving them would bring him closer to what he wanted to know. After this fun talk we waited in line to meet the unexpectedly candid and easygoing figure that was Rai Weiss. We eventually got to meet him and he obliged us with autographs and a short interview. He told us that the most exciting result of the LIGO discoveries is that Einstein’s field equations work over a wide range of field strengths, and he revealed to us that his spirit animal is a pussy-cat.
“The Einstein field equations work over a dramatic range of field strengths. They explain why you’re standing on the ground and they explain how the Sun holds together, and they also work at the edge of a black hole… That’s amazing, and it was all done by something in [Einstein’s] head!”
And with that exciting revelation we retired to our hotel rooms.
My name is Levi Schult, and I’m also a first-year undergraduate student at the University of Virginia, and this is Sunday from my perspective. On Sunday, we attended the Society of Physics Students career workshop breakfast and learned about paths for success in fields outside academia and graduate school with a physics major. We then attended several talks from pulsar astronomers who were a part of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) collaboration. We learned about how uncertainties in Jupiter’s orbit, and therefore the solar system ephemeris, has created false a signal of gravitational waves in NANOGrav’s pulsar timing data. Dr. Jeff Hazboun spoke about “kinks” in the millisecond pulsar data set and possible causes such as the change of data processing back ends. He also talked about sophisticated dispersion measure modeling and correlations with the solar wind, “We found Jupiter and we found the Sun,” he said. Dr. Sarah Vigeland spoke next about a somewhat problematic pulsar, specifically J0613-0200, that was creating a bump in the dataset. This bump disappeared, however, in the 11-year dataset, as the collaboration added more pulsars to the dataset and improved sky coverage. Dr. Vigeland also displayed how limits on detectable gravitational waves could be developed as a function of frequency and sky position. Dr. Paul Baker was the last NANOGrav speaker in the session and he talked about the sensitivities of pulsar timing arrays in general along with the collaboration’s in particular. Gravitational waves produced by bursts with memory gravitational waves pose an especially difficult problem in detection as they are covariant with the timing model of the pulsar and a pulsar’s response to a wave of this type is dependent on the sky position. Many more pulsars have been added to NANOGrav’s dataset recently, and as a result the array’s sensitivity is dominated by the more recent years. He noted that the sparse observations and lacking backends in the early years of NANOGrav also contributed toward this lopsided sensitivity in time. The talk ended with goals of improving noise modeling and sky coverage with the second data release from the International Pulsar Timing Association.
The undergraduate pulsar timing group then presented their poster and fielded questions from other attendees at the meeting. We interviewed Dr. Nicolas Yunes, an associate professor at Montana State University and the co-founder of the eXtreme Gravity Institute.
He explained to us his surprise at the LIGO detecting a binary black hole merger first when binary neutron stars mergers were predicted based on current observations.
“In hindsight everything is 20/20 and of course the first time you turn an instrument on you’re going to hear the loudest events first, and the loudest events are by far black holes with a large mass colliding with each other.”
He talked about how his focus in astronomy began with black holes and their gravity and is now moving toward neutron stars and pulsars.
We also interviewed another undergraduate presenting a research poster named Osase Omoruyi. Omoruyi is a third-year undergraduate at Yale pursuing a degree in Astrophysics. She presented a poster on interstellar bubbles and their relation to the inefficiency of molecular clouds in creating stars. Omuruyi’s research was also heavily dependent on citizen scientists searching for traces of bubbles in the interstellar medium. Talking about choosing an area to specialize in, Omuruyi said,
“I’m very torn, I really don’t know at this point but I think it’s okay because graduate school is where you’re supposed to figure that out: I don’t need to decide that now.”
I think this is one of the most important things I learned at this conference. I am very undecided in the field I would like to specialize in as I find it all interesting but I am going to use my time as an undergraduate to explore many different fields within astrophysics.
My name is Matt Walker and I am currently a fourth-year student at the University of Virginia. My research interests are in Condensed Matter Theory and I presented a poster on the research I have been conducting under professor Jeffery Teo. After Levi and Morgan left Columbus to go back to UVA I was on duty for the third day of the conference on Monday. The first series of talks I attended was “Mathematical Aspects of General Relativity.” I chose to attend these talks because I am currently taking a course both on General Relativity and Differential Geometry, and I was curious to learn about the current research that is happening in GR. Surprisingly, I was able to understand almost all of the talks. However, there were two talks that really struck me as interesting. The first was talk given by Gatum Satishchandra, a graduate student at The University of Chicago. He talked about his current research studying the memory effect in odd dimensions greater than four. In a recent paper that Gatum wrote with his PhD advisor Robert Wald, they proved that the memory affect doesn't not exist in spacetime dimensions greater than four. It was previously known that memory effect does not exist in even spacetime dimensions greater than four, but thanks to Gatum we know understand that it doesn’t exist in any odd spacetime dimensions greater than four either. This begs the question to why it manifests itself in our four dimensions? There is more research to be done on this topic and I’m confident that Gatum will continue investigating.
The second talk I found even more interesting was given by Dr. Leo Stein, a postdoc at Caltech. His talk was titled, “Black hole scalar charge from a horizon integral in Einstein-dilation-Gauss-Bonnet gravity.” I was excited about Dr. Stein’s talk, the minute I read his title and abstract. As I am a huge fan of the Guass bonnet theorem and I was surprised to see it appearing in a GR talk. It turns out that a large part of testing GR is studying theories that almost resemble GR but are slightly different. In this case, Gauss-Bonnet theorem adds an extra symmetry and allows researchers to explore the consequences of adding this symmetry. In Dr. Stein’s talk he illustrated how in beyond GR theories with a scalar field, a black hole’s scalar charge is perfect for testing the theory. In the special case of Einstein -dilation-Gauss-Bonnet theory the scalar charge can be extracted from a horizon integral. Dr. Stein showed how he did this and what results he found. At some point he referenced one of his older papers he wrote with his colleague, Kento Yagi. Coincidently, Dr. Yagi is my professor for General Relativity. I thought this was rather funny so after his talk was over, I asked Dr. Stein for an interview. He was more than happy, and we after we found somewhere quiet I asked him more about his research. I asked him about what problem he was trying to understand and what the motivation was behind the talk that he gave.
“I think of theories that are not General Relativity but are somehow are closely related to General Relativity...This one particular theory that has Guass-Bonnet in it is fun because the fact it has this topological invariant in it, it has an extra symmetry and it allows you to do the type of calculation that I did which relies on the shift symmetry to compute the black hole scalar charge.”
I also asked him about how to get the most out of a conference like APS April meeting since it was the first one I attended.
“I look at what’s scheduled for the next day and I pick a session for each time slot for each talk I want to go to so that I’m not running around and I know what’s going on in the field.”
After the GR talks were over, it was time for my research group and I to present our poster during the research poster session.
While I spent some time presenting my poster the other conference goers, I left my research partners in charge for most of the session so I could interview some of the other students and scientists. One the posters that caught my eye was a poster on the local hidden variable problem in quantum mechanics and was being presented by Melissa Schmitz. Melissa is an undergraduate from Le Monye College, and I had the chance to interview her.
I asked her how many conferences she has been to and also what she usually does when she goes.
“This is my 9th conference or something, I’ve lost count. I think presenting is one thing, but not everyone has research yet and I think it’s important that students that don’t have research yet should go to conferences... Other ways to get stuff out of conference is to plan ahead and see what interests you and go to as many sessions as you can so you can get the most exposure to what’s out there. Networking is really important which is kinda hard but poster sessions help and going to the undergrad events is really useful.”
Lastly, I decided to interview a PhD student named Bashar. Bashar was presenting a poster on the work he did at Jefferson national laboratory. I chose to interview Bashar because Jefferson Lab is very close to where I grew up, and I have visited there many times. I asked him about what it’s like working at J-Lab
“I was there to do research towards my PhD thesis, I loved it there. It’s hard, you have to work as much as you can to survive.”
Bashar was an international student and so I asked him if he had any advice for students who were thinking about going to graduate school in the United States.
“If you wanna come over here you should work as hard as you can, especially because two things, it’s a new culture and the English language.”
This was my first APS conference and overall, I thought it was an amazing experience. I met some awesome scientists and fellow students, and I got to present my research that I have been working on the past year. I look forward to attending the APS March meeting next year.
In some recordings you can hear Matt’s colleague Victoria’s voice. He asked her to come with him and do the interviews so it wouldn't be such an awkward one-on-one experience.