physics research at penn 🔭

a short guide to the department and how to get involved in research

Let’s do some research

As someone who had very little coding experience and even less research experience, getting my foot into the door in Penn’s physics department was pretty daunting. Here are some good things to know.

The department

The department’s interests are divided into three main categories: astrophysics and cosmology (the big), condensed matter (the small), and particle physics (the really small). Notably, these three categories do not include physics research being conducted in other schools (like school of medicine / engineering) or departments (like chemistry).

There’s a good mix of theorists (who theorize) and experimentalists (those who probe reality) for each research subject, although I’d bet that there are quite a few more experimentalists than theorists in the department. Since undergrads usually only work on experimental research as the learning curve for the theory is pretty steep, I’ll just be talking about that.

Astrophysics and Cosmology

Lots of faculty doing data analysis on large survey datasets like LSST’s Dark Energy Survey, developing instrumentation for telescopes, and lots of simulating things like galaxy formation and evolution. Super cool and usually computational with lots of Python. If you find machine learning cool, there’s a bunch of it happening here.

Examples of undergrad research:

• Computational: Working on machine learning approaches to identifying supernova in large-scale galactic surveys or inferring dark matter distributions in galaxies via fitting mathematical models to simulations and real data.
• Hands-on: Helping to engineer instruments for a high-altitude balloon-borne telescope.

Condensed Matter

We have one of the strongest condensed matter groups in the world. Lots of interdisciplinary research here across other subjects like biology with living matter and engineering with quantum materials science and centers like Penn’s Singh Center for Nanotechnology. Home of the birth of the “fourth state of matter,” topological insulators, by Dr. Eugene Mele and Charles Kane. Crystals, many-body systems, physical network formation and topology, etc.

Example of undergrad research:

• Developing and testing optical techniques to study and control properties of quantum materials or working on simulating complex animal blood vessels and the topology of the network created.

Particle Physics

This group tries to understand the fundamental structure and effects of subatomic phenomena. A very strong group of particle physicists mostly working on larger collaborations and experiments. We have faculty working on the ATLAS project at the Large Hadron Collider at CERN and many neutrino experiments like SNO+ and the future DUNE experiment at Fermilab, contributing much to R&D efforts in detector electronics, data analysis, and simulations. Lots of Python and ROOT.

Examples of undergrad research:

• Computational: Create or help improve algorithms that reconstruct subatomic particles’ positions, directions, and energies from data in particle accelerators like LHC’s ATLAS.
• Hands-on: Work on testing and enhancing new instrumentation for neutrino detectors.

Ways to get involved

First, sign up for the weekly CURF (Center for Undergraduate Research and Fellowships) newsletter. It’s a great way to stay up to date on research opportunities, fellowships, and other cool research-related things happening at Penn. Much of what I’ve learned about research opportunities at Penn has come from this newsletter.

Much of the faculty is super enthusiastic about undergrads working in the lab, so there are thankfully a ton of ways to get into research at Penn. I’ll go through each one here, from most-used to least-used.

1. Peer Undergraduate Research Mentorship (PURM)
   apply late February
   This program is made for students with little to no research experience wanting to give it a try. You get a stipend for conducting research with faculty over the summer, and the faculty gets a nice grant for taking you on. An application is required, but there are no letters of rec. and all you have to do is write about why you want to undertake whatever project you’re applying for. There are usually ~5 faculty members of the department who take on students with PURM every summer. Definitely the easiest way to get into research at Penn.

2. CURF Research Directory
   apply Spring semester (usually)
   On the CURF website, there’s a directory full of faculty members who have said that they’d be open to possibly taking on undergrads in their lab. This doesn’t mean that they’ll take you as you both need to be a fit with the lab and your PI, but the door is open. Email them stating your interest in their research and the possibility of contributing to their research program down the line. A little scary, but it’s at least nice to know you’re emailing someone who is open to having people like you in their lab.

3. Cold emailing
   apply Spring semester (usually)
   This can be pretty daunting, but if you’re really interested in a certain faculty member’s research, you should totally email about it. This was the approach I took, and while there was a lot of trial and error in the email writing, it all worked out. Faculty usually like taking on students during the summer as it takes weeks for undergrads to start to become productive, and even more if they’re taking classes, so it’s usually good to cold email during the Spring with your eyes set on the summer. Getting paid is a little harder as you’re eating your PI’s grant, unless you’re work-study eligible.

   If you’re having trouble getting started, email me and I’d be happy to help you out.

4. Student Employment Office Job Directory
   apply whenever
   There’s an online job board at Penn that a few faculty members in the department post available research positions for both work-study and non work-study undergrads. Here, they are literally looking for someone to work with them, so if you see a post by a faculty member whose research you find super cool, you should absolutely reach out.

Word of advice for Penn opportunities:

Go through the physics faculty directory and find faculty members whose research you find interesting. Then, go to their personal websites and read about their research, maybe gleaning through the abstracts of some of their recent papers. If you find any of it interesting, email them about it. It’s a lot easier to write an email to someone whose research you find interesting than someone whose research you don’t.

Also, don’t be afraid to email multiple faculty members at the same time. It’s a numbers game, and you’ll likely get a few responses back.

Non-Penn opportunities

1. NSF Research Experiences for undergrads (REUs)
   apply early Spring semester
   REUs are one of the best ways to get introduced to physics research. Universities and institutions like the American Museum of Natural History take on undergrads from all over to conduct research for a summer. It’s a great way to get some experience outside of Penn, or in another subfield of physics you’re interested in. Much like PURM, this is one of the programs I highly highly recommend applying to. For a good resource that compiles each REU and their description, check out reufinder.com.

2. Department of Energy’s Science Undergraduate Laboratory Internship (SULI)
   apply early Spring semester for summer internship
   This is the same thing as an REU, except that you will be working at a DOE-sponsored national laboratory. Working for the Department of Energy might feel a bit odd, especially if you’re not interested in energy, but the DOE funds much of US-based research in physics, chemistry, and biology. I highly recommend this as well; you may end up working at Brookhaven National Lab (BNL) in Long Island, Fermilab near UChicago, Lawrence Berkeley National Lab (LBNL) at UC Berkeley, SLAC at Stanford, the Princeton Plasma Physics Lab, and more. Many members of these national labs also have appointments at nearby universities.

3. Caltech’s SURF/WAVE Fellows
   apply early Spring semester
   An REU experience at Caltech, working with some of the most distinguished scientists in the world. Very very competitive (as is everything else), but an amazing experience. SURF is a general REU-like experience, while the WAVE Fellows program is created mainly for under-represented minorities.

Word of advice for Non-Penn opportunities:

• Contact potential mentors before applying to see if they are willing to take you. There’s no reason in applying to a closed position, and reaching out to faculty members shows initiative.
• Check out the Penn physics majors Slack channel for alumni who have attended these programs and have fantastic advice you can learn from.

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Cool classes

Here are cool classes I’ve taken or have heard of for physics majors.

1. PHYS 260 Computational Physics: Taught by the legend Dr. Bob Johnson. Amazing class, gradual introduction to the Python language and using it to solve physical problems. No tests, just homeworks and a final project. Highly recommend for a first or second year who doesn’t know Python or is interested in comp. phys.

2. PHYS 280 Physical Models of Biological Systems: Haven’t taken this class but if I liked bio I would have by now. Taught by Philip Nelson who literally has a book called Physical Models of Living Systems. He also wrote the textbook we used in PHYS260.

3. PHYS 358 Data Analysis for the Natural Sciences: Introduction by the amazing undergraduate chair Dr. Masao Sako to statistical analysis of data. Super helpful for anyone into research. Bayesian and frequentist methods, PDFs, negative log likelihoods, etc. No tests, just homeworks and a final project. I took it F20 and would recommend it for anyone who isn’t too good with statistics. Python-based.

4. PHYS 359 Machine Learning: New class on ML taught by the great Bhuv Jain. Super similar to 358 in that a lot of statistical foundations are built before moving to ML. Logistic regression, random forests, dense and convolutional neural networks. Final project was classifying galaxy types from actual images from the Sloan Digital Sky Survey (SDSS) with machine learning.

Groups on campus

1. Society of Physics Students (SPS): General club for physics majors
2. PennGRAD: Physics grad students helping undegrads get into grad school
3. Penn Astronomical Student Association (PASA): General club for students interested in astronomy’
4. Women in Physics (WiP): General club to advance women in the pursuit of physics and physics-related fields.
5. Diversity & Inclusion in Physics: General club that strives to make the physics community more inclusive.
6. AI@Penn: Non-physics group focused on AI and ML
7. Penn Data Science Group (PDSG): Non-physics group focused on data science
8. Penn Aerospace Club (PAC): Non-physics group focused on aerospace

Things to do when you’re in research

1. Apply for University Scholars
2. Give talks at APS/other conferences/Penn CURF events
3. Participate in group meetings
4. Become an RPA!