Absolutely. I read up on a lot of science, and even chug through text books. As robryan says above though, reading a book on chemistry or functional analysis is

Absolutely. I read up on a lot of science, and even chug through text books. As robryan says above though, reading a book on chemistry or functional analysis is long way from being ready to do research in the field. One of the reasons I chose applied math was because I thought it was the best centralized position in all of science. It would take me years to switch to another branch of math, but in applied math I can at least switch the focus of application, possibly in under a year or two.