Darshil_IITB said:
I am currently a 2nd year UG student pursuing B.Tech in Engineering Physics at IIT Bombay. What are the various sub-topics of physics that are used by a biophysicist? Percentage wise, how much physics is exactly there in biophysics? Where should I start from if I want to become a biophysicist?
Statistical mechanics, as has already been mentioned, is the most important.
The amount of physics in biophysics varies. My group is closer to biochemistry in some ways. We take a set of specific proteins, and we would like to learn more about how they function, which is a biological/biochemical question. A different group on my floor works on, among other things, phenomenological problems regarding optical spectroscopy and biomolecular solvents, which smells more like physics.
The two most "physicisy" types of biophysics I can think of are either the study of photosynthetic proteins, which involves sophisticated quantum mechanics, or sampling problems, which sounds quite boring, but in fact involves extremely sophisticated statistical physics. Some people who work on non-equilibrium statistical physics, which is an unfinished field of physics, also work on non-equilibrium methods of biophysical simulation.
Non-equilibrium statistical physics can even get pretty esoteric:
http://www.theory.physics.manchester.ac.uk/~ajm/mv04.pdf
EDIT: Lest we forget, protein folding is still an unsolved problem. Note that even if a biophysical problem doesn't involve much esoteric physics, it will still involve extremely non-trivial computational problems which keep things very interesting indeed.
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