Cosmology: a good career choice?
I know this is kind of old, but I wanted to give my experience and advice.
Study what you want. And if you can't get a job in that field, you can get one in a different one. I studied physics and math at CU-Boulder for undergrad. Once I was done. I had several job offers (this was only after a B.A.). Part of it is location. Boulder had a bunch of labs. I doubt I would of had a lab job offer if I wasn't local and had local connections. So, try to pick a school with a lot of industry/research labs close by. I also had a finance/actuarial job offer. This was insanely high paying for a starting salary. Probably slightly low paying for the field. But after eating ramen, I had no idea what to do with this amount of money (well except school loans). The trick is to know what type of finance jobs to look for. Forecasting or actuarial firms love mathematicians and physicists. These majors were picked over finance majors and we didn't have to study finance. While in school just take the first two actuarial exams, you at least won't have to worry about unemployment. I learned about this from a math Ph.D who went there during my time at CU.
So, from my experience, if I got a degree in something I didn't like, I wouldn't be any better off. I just wouldn't have learned what I wanted to learn. This is true for Ph.D students too. The actuary salary I was offered was more than my sister's law salary. So, just going to law school or some other field for employment prospects makes little sense to me.
And if you were wondering, I decided to go to grad school. And while in school am working to teach high school. I took a completely different path. But, I think there is something to be said about following your passion or jobs that you like. That is the best advice I ever got from a professor.