In my undergrad years in physics (1971-1975, University of Hawaii), I had not worked on any particular projects in physics except the laboratory courses. For my master’s degree at Arizona State University (1975-1978), I engaged in projects related to experimental solid-state: physics electron diffraction and imaging configuration in electron microscopy. For my Ph.D. at Stony Brook University (formerly State University of New York at Stony Brook) from 1978 through 1984, I engaged in x-ray diffraction/crystallography as well as theoretical modelling of the elastic properties of minerals (crystalline solids of geophysical interests) based on a mathematical theory/technic I developed. All these were basic research. As a postdoctoral fellow at the Carnegie Institution for Science (1984-1985), I continued my work from Stony Brook University.
Then, I left academia to work as a scientific consultant for NASA from 1985 through 2005. I performed both basic research as well as R&D projects. At first it was a project related to radio-astronomy. Gradually, I migrated to terrestrial geophysics and then to space-borne geophysics. Later, I moved onto space geodesy/satellite tracking working with global climate data. My work was interdisciplinary, and I had to work with scientists of various fields. We worked well together to make it a very fruitful endeavor.
I left scientific consulting back to academia in 2006 as a professor of mathematics and statistics, and retired in January, 2020.
My friends from grad school are mostly still working in physics - most are professors teaching at university and doing research. A few are working at laboratories and get to do (or manage) research all day long. They seem fairly happy with their work.