Planning for physics PhD apps - Classes vs research? Question: I'm planning for PhD apps a year from now. Do I skimp on classes and further research, or do I further my studies to learn the theory that I personally want to develop?

Some background... I'm a physics masters student in the US. Technically, this is my third year in the program as my bachelor's degree was not in the sciences; I've essentially completed an undergraduate degree worth of prereqs. I'm taking grad courses now. The school is not renowned, but it has a history of physics research. (I was unable to compete with stronger schools due to my lack of prerequisite knowledge a few years back). Anyway, I'm a rather strong student (4.0) with some research. Nothing is published yet, but I'll be hopefully named on one paper in the spring. I'm looking to apply to top 40 schools in mathematical physics or applied mathematics, and professors have said I have a good shot.

My research adviser is pressuring me to take fewer classes and focus on research next semester. I'm conflicted, as other professors have suggested that this is the class to take! The course my RA suggests I drop is E&amp;M Jackson. I want to learn this material, and I find my studies more compelling than my current research. My RA argues that if I drop the course, then I can commit more time to research, and furthermore, I have less chances to receive a poor grade that could alter my GPA. My RA goes on to suggest that schools do not care whether I have yet to take certain courses like E&amp;M.
Research experience and track record is more important than courses you have taken.  You will very likely be required to take Jackson E&amp;M for the PhD program.  You might be required to repeat it if you took it before, depending on the program's rules.  Keep in mind that classes you take (or research you perform) after you apply for the PhD program usually do not change your admissions decision.

In sum, I recommend postponing the E&amp;M course.