I've started a phd in fluid dynamics. I always wanted one in general relativity or quantum field theory really, I got interviews for that (many really) but none where successful, I got into fluid dynamics straight away so after waiting around I thought I should crack on and maybe it's meant to be. I do not hate my PhD, but I do not love it either. Whereas if it was general relativity or quantum field theory I think I would really really enjoy it. I am now around 8 months in. I enquired about a phd in cosmology/gravity theories a while back, more out of curiosity, and I received this advice back from the professor at a different university. I had not thought of this idea probably cause I thought the other departments would not be interested in the slightest. I am currently in the engineering department. Does his feedback seem infeasible or is it worth a shot? (I am not sure right now if I will apply for cosmology/gravitational phd in a month or so, when application time begins to peak, if I see the right project..part of me still really wants to, part of me thinks I may as well stick to what I've invested time and work into)

FEEDBACK:
I can’t really suggest what’s best, except to discuss your current situation and your ambitions with
your supervisory team. XXX YOUR UNI XXX has some world-class activity in computational cosmology, and it may
be possible for some sort of collaborative project to be worked out. If you’re 4 months in (and what an extraordinary 4 months)
then there is still plenty of time for things to develop


Re. my current funding:

have two assigned supervisors. the scholarship is from the engineering department, not the maths or physics, so I doubt that would be able to directly switched over. However the main supervisor had full control over this scholarship (he was awarded it when he arrived at the university ), so if he agreed on a intersection with a supervisor within the maths/physics department it may be possible. But I also dont want to pee off my current supervisors, if they would not like to grant permission for such a thing, in particular say.