I'm a sophomore physics major, but I'm having trouble figuring out what where I want to focus. I started out in biological engineering but realized that it was WAY to specialized, and I'm enjoying the freedom of the physics program much more... though this may eventually backfire. I am mainly just looking for some advice from people with experience. Basically, I'm most interested the interdisciplinary fields of physics such as biophysics and geophysics. I'm not all that interested in staying in any of the "traditional" fields of physics because I feel that the tools of a physicist can be used to solve other interesting problems outside of physics. It seems like I'm more interested in the "tools" and the problem solving more than anything. I chose physics because I like the way they learn to think, and I want to have that background. This uncertainty about where I want to focus has been stressing me out, especially when I think about graduate school, etc. My dream scenario would be to work on many different problems in many different fields. I heard of a few people doing this, but more often I hear that it is best to choose a narrow topic of one field (niche field) and become the worlds leading expert on it. This does not sound appealing to me at all.. More specifically, I've read about people in chaos working on problems in everything from geology to ecology to atmospheric science, and that is ultimately what I would like to do. My question is, how hard is it for someone with a physics background to work on other problems and not necessarily specialize in one area. I'm guessing that studying nonlinear dynamics would apply to many fields, so would this be a wise area to pursue?