If an event has free food, you should attend—this is something any student knows. So when my undergraduate alma mater invited me back to give a talk (and promised free food), I said yes.

During my time as an undergraduate student at Moravian College in Bethlehem, Pennsylvania, I was involved in the school’s Society of Physics Students chapter. As a senior, I was elected president of SPS and Sigma Pi Sigma. The purpose of my recent return was to give a short, informal lecture on my experiences as a graduate student.

I am currently a graduate student at Temple University and a member of DarkSide (http://darkside.lngs.infn.it/), an international collaboration of universities and labs working together to detect hypothetical particles called weakly interacting massive particles, or WIMPs, that could solve the dark matter problem. When I gave the talk, I had not begun any intense research, so half of my presentation was about adjusting to grad school and half was about doing research and teaching in grad school. I also discussed the work that previous students in my lab accomplished on the WIMP problem.

Dark matter, as I told my undergraduate audience during my talk, is a form of matter that balances some equations of classical mechanics that describe how galaxies rotate. To explain what is seen in the rotation curves and thus make the equations work out properly, most of the matter in the universe must be dark matter, i.e., stuff that does not emit light. This surprised some of the undergrads in the audience. They wanted clarification on why dark matter was necessary. They wanted to know what dark matter was made of. They wanted to know if there were any alternative theories that would make dark matter unnecessary.

I tried my best to answer their questions, impressed by their level of interest in the subject. The experience reminded me of lectures presented by SPS alumni while I was still in college—including the first time I learned about vortex lattices in superconductors—and bolstered my faith in the future of the physics department at Moravian, which is clearly still inhabited by inquisitive minds.

After I completed my bachelor’s degree at Moravian, I was concerned about how my chapter would fare. Keeping a group of students interested in an academic organization such as SPS can be difficult. Moravian is a small liberal arts college; at times, some of the organizations I was involved in had so few members that you could count them on one hand. It was a fantastic feeling to return to my alma mater and find that things are going just as well—if not better—as when I left them.

Keeping in touch once you’ve graduated can be difficult, as you focus on new responsibilities and relationships. But it’s worth it! It takes minimal effort to send an e-mail to your old SPS advisor asking how things are going. Professors like to know that their students are doing well postgraduation; after publishing a paper in Physical Review D, I made contact with a few of my former professors. It was nice to find out about the current construction going on to improve the natural sciences building at Moravian, to learn about how a recently retired professor was faring, and to keep in touch with the people who had nurtured and strengthened my interest in physics. I’ll be sure to e-mail them again sometime soon, or maybe stop in for a visit when I’m in the area.

Of course, giving colloquia at your alma mater is also a fantastic way to see how the department is doing, catch up with your old professors, and check in on the students. In my experience, most universities welcome alumni speakers, but you just might have to take the first step. Who knows, you may even get some free pizza out of the deal!