Which PhD program should I choose - cosmology or quantum optics?

[susskind_leon]

I got my degree in physics some months ago and I want to start a PhD asap but I'm still undecided about my specific area.
The situation is rather tricky: I would say that my research interest lies within statistical mechanics or condensed matter theory, because I think it's something profound, useful, yet as theoretical as you like and ultimately, you can use computers to tackle the problems, which I generally enjoy a lot. Yet, I don't want to leave my city (yet), which limits my options.
Here, it's all about particle physics, but I don't want to do particles for sure.
There is one position for me in a group that does cosmology. They do a lot of computing on galaxy observations and also, it seems that cosmology has some overlap with statistical mechanics, right?
Also, there are a lot of people here working in that area which gives it a somewhat vibrant atmosphere.
There is also a group which does quantum optics. They occasionally work on fields like BEC, polaritons, laser physics, ... so in terms of overlap, I would probably be more . The only thing that makes me hesitate to take this position is that the group is really small and isolated and I know from personal experience that work is only half as fun if are alone.
So... what should I do? Is there a chance to make the transition cosmology -> Solid state / stat. phys.?
I'm relatively sure that QO is a better choice in terms of my (current) research interests but the environment is rather uninspiring / lonely and that I would probably stay at home a lot and maybe just come to the department to discuss with my advisors and leave after that, just like their last PhD student did (who has done a really good job there)

 

[R.Mesri]

It is difficult to make such a decision without knowing more details about the specific research areas and what projects you would be working on. However, one of the most important factors in choosing a PhD program is finding an advisor with whom you get along well and who can provide the support and guidance you need to reach your goals. In terms of research area, it is possible to make a transition from cosmology to solid state/statistical physics, but it will depend on the specific projects you are assigned. Make sure to talk to both advisors in detail about the projects that you will be working on and how they overlap with your research interests.If you are really passionate about statistical mechanics or condensed matter theory, then the quantum optics group may be the better choice even if it is smaller and more isolated. You can always try to find ways to socialize outside of work, such as joining student clubs or attending local seminars and conferences. Ultimately, the most important factor is having an advisor who is able to help you reach your research goals.