Is there something I could do considering I'm not really happy with my master's thesis? On the begining of this year I've started a graduate course in Physics to obtain a master's degree. I have a major in mathematical physics and mathematics and wanted to work with General Relativity, Quantum Field Theory on Curved Spacetimes or related topics, but with focus on fundamental physics. In particular I'm quite interested in the infrared structure of gravity and gauge theories and the application to soft hairs on black holes.

There was a professor that was going to advise me on a very nice project about black hole radiation, but unfortunately he passed away. I started then searching for another one, but the ones I found were from the math department and was quite hard to get a permission to have them as advisors on the physics department.

I was talking to two of them, one of which was my advisor in a undergraduate research project. He didn't work with what I wanted but proposed one work on extended bodies in GR, but he didn't tell much details. It didn't interest me but said it was interesting just to be nice.

The physics department ended up allowing some students to have advisors from the math department. The one that could advise in what I wanted needed to advise someone else. This other professor and the coordinator ended up "assigning me" to work with the extended bodies work professor.

I wasn't feeling good about it, but I was being pressed by the deadline to find one advisor and, because it was already one exception, I felt bad to refuse and accepted in august.

I'm working on this for three months now and I can say I'm not fully happy about it. I have quite a few complaints:


It is not fundamental Physics and it is not what I would call GR. It is dynamics on GR. Up to now I've studied two papers and no deep thing about GR was needed. Some students say they discussed with their advisors for quite a long time what would be done. In my case I was handed what should I do.
The advisor requires that the work be devoted to computing examples, like solving a really hard toy model. He find this extremely important but I can't see it like that.

I didn't want that, and I know it is not a requirement. I've seem master's thesis from there and other universities focusing on the fundamental physics aspects and the structure of the theory.
My advisor doesn't know the theme. I have to study the papers alone and present seminars twice a week so he and another student of his can learn the subject. This is making me feel extremely pressed because the papers are very hard and I have not much interest.
Although studying the papers for learning more about how extended bodies can be dealt with in GR is something I would happily do in my free time, dedicating that much is preventing me from studying what I really want to do afterwards. I believe this combined with how much I'm being pressed is the big deal.


The issue is: I'm on this for four months now and I feel it is too late to do something. I think that if I go search for another advisor they'll say there is too little time left (one year). I don't even know if I'll find one. If my advisor finds out I'm searching for another one it could also create a difficult situation I think.

Plus, I don't want to offend my advisor or start a fight, after all, he is a good person. It is just that for all this time I felt embarrassed to say I wasn't really interested in this, and I feel even more embarrassed to say that after all this time. I've tried implying a few times I'm not interested, but he didn't understand I think.

What can I do in this situation? I mean, is there some option other than continuing with this even being unhappy? Is there some way to change things, without offending anyone, starting a fight or creating an embarrassing situation? I need some piece of advice.
Have an honest conversation with your advisor.


  I appreciate the support you have been giving me, but I have to be honest that I'm getting increasingly frustrated with my project.  This isn't the area that I hoped to work on, and I'm struggling to really get into it. 


Note that this is nothing against your advisor.  Be careful not to frame it as a criticism of your advisor; it's about this project's fit to you.  If you put it this way, it shouldn't be offensive.

Also, presumably your interest now is also your interest for your career path in the future?  If so, I would highlight the impact of that:


  In addition, I'm hoping to go on to a [PhD/career] studying [fundamental physics--insert the appropriate term here.  I'm not a subject expert]. I'm worried that I'm not developing the skills and expertise I need to move in that direction.


In my mind, this is the most important point.  If it's just a matter of enjoying your current project, sticking it out for the next year might be the best option.  But if your current project is limiting your future options, it's important to address.

After sharing your concerns, what to do about it?

If at all possible, I would try to explore with your advisor whether your project can be tweaked to better fit your interests.  Could it focus more on theory rather than computing examples?  Could it bring in some other related thing that is more what you want to look at?  Again, I'm not a physicist, so I can't help you on the specifics. The cost of changing projects would be high.  It's preferable to modify the current one if at all possible.  

It sounds like so far your advisor hasn't been very flexible.  However, given that you accepted a project and worked on it for four months "just to be nice", it also seems likely that he doesn't know how you really feel about the work.  Perhaps he will be more flexible once he understands.  

If there isn't flexibility, then you have a tough decision: take the "safe" route of completing your current project, or try to switch projects (and probably risk delaying your degree).  But I would try this as a first step.