I’ve gotten a few questions from my adopters on when I decided to study physics. I had actually made that call in high school, so I went into college already having declared my major. I didn’t really know what a physicist did, but the subject was more interesting to me than the other science classes I had taken, and the thought of what I would do with the degree hadn’t yet entered my mind. My parents encouraged me, but they didn’t have a science background, so that was a general push toward learning and not so much in the direction of science.
Bad teaching wasn’t a factor in my decision. My middle-school teachers were good, and in high school I had a good teacher for earth science, but the material didn’t excite me tremendously. I had the same teacher for chemistry and my first physics course, so there was no bias there. But there were parts of chemistry that just didn’t click with me. Being sick and missing a week of school while we were learning LeChatlier’s principle didn’t help. Trying to learn new material while being spotty on basic concepts is a huge hurdle to overcome. Biology was eliminated very early in the game — I never took it in high school because a dissection was something that would make my joints and muscles turn to jello, and then there was the propensity to be ill. Yuck! I do enjoy learning about biology-related things like evolution and paleontology, just as long as I’m not exposed to greasy grimy gopher guts or the equivalent.
The other thing pushing me toward physics was my next-door neighbors. The father (Mr. H) was an engineer and he had a son (Tom) who was a few years older than me. We did several projects that were physics-related, though I didn’t really know it at the time. Mr. H loved steam engines, locomotives (especially steam-driven ones) and dams (hydro power, either electrical or mechanical), and I recall going on outings to see all three kinds of things. They had a small steam engine model (one mousepower) that we played with, as well as some other “toys.”
When Tom started taking physics and learned of the monkey-and-hunter problem (monkey in tree, and drops as soon as you shoot — where do you aim? Right at him, since gravity pulls both the monkey and bullet down at the same acceleration: g) we set up an experiment in his basement. A blowgun and a target that was attached to an electromagnet, and would drop when the dart left the barrel of the blowgun (the dart touched a thin wire that completed a circuit and opened a relay) and sure enough, if you aimed at the target, it would generally hit it. I was hooked. Even though formal instruction into basic physics was sometimes a little dry, I kept with it, because of the hints of really interesting things later that paid off.
Okay, so when did you know what field/subfield of physics you wanted to go into? Did anything count in that decision beyond just what you were most interested in?
I had eliminated solid-state and nuclear/particle by the time I got to grad school. Working with lasers and atoms seemed the most interesting, and I was fortunate to get into the really interesting area (to me) of laser cooling and trapping. I was actually only planning on an MS at the time, but my personal situation changed (I got dumped, so had no pressing need to be done with school in 2 years), and my “friends” who were already in grad school convinced me that as long as I was there, I should stay and get my PhD.