I have a choice between Physics and Biomedical science
For the purposes listed in the title, obviously biomedical science.
Would the physics not provide me with a stronger background though? As in for the nanotechnology parts?
In computational biology and the other fields you are talking about, the main focus will still be on the biology part. You'll just be using methods from other disciplines.
Depends. In the case of computational biology, it's an interdisciplinary field. For a biologist it could just be a tool set, but you have physicists, mathematicians, computer scientists developing those tools and collaborating with biologists in order to test their models with experimental observation.
Also with only an undergraduate degree you'll only be a research assistant. And for those types of openings "computational biology research associate/assistant" I've only ever seen them require quantitative disciplines like physics, math, statistics, and computer science. Experience with software packages like MATLAB and R are usually some of the main desired skills.
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