When is it advisable to switch PhD projects if you are not making progress and have a promising alternative project? Is it worth going from guaranteed research assistantship funding to less reliable teaching assistantship funding?
I've been working on a particular funded research problem for 2 years now. So far, I'm still trying to reproduce previous results and learn. I am making progress, but it's very slow and frustrating. I don't anticipate finishing a PhD on this topic in less than 5 years, and think 7 or more is likely. At this point I am frustrated with this project and losing motivation.
This is mostly due to certain unanticipated faculty changes at my university. I originally came to work with 2 professors in a field that overlaps with both of their previous research. Unfortunately, one of these professors left and has declined to participate further. Had this professor stayed, I'm confident I would have made a fair bit more progress already. My current advisor is capable, but they freely admit they are far out of their comfort zone with my project. I'm making many basic mistakes that would be easily recognized and fixed if my advisor was more knowledgeable on my topic. My advisor has tried to interest other faculty in the project, but unfortunately none at my university consider themselves adequately competent in the subject to advise.
For fun, I recently published a paper on a particular solution to a problem which grew out of a homework assignment. I have received a surprising number of positive comments on this side project so far and see many research opportunities in this field. This topic fits my advisor's capabilities much better than my current research topic.
I think I'm at a juncture where switching projects may be a good idea. I discussed this with my advisor, and they said either way is okay with them, but I think they are leaning towards me switching. We have no funding for the second project, but my advisor thinks it's worth trying for a grant application and they told me they would support me financially either way (even if it's making sure I get TA positions).