@KGZoTU: Every math major I've interacted with has been exceedingly pleasant. You'll definitely get the academically intense but respectful environment you want. Re: political sterility, it's really up to you as to how politically active you want it to be; most math majors that I've spoken to are not particularly interested in politics, (especially when compared to math
) The Math library is fairly quiet, the engineering library nearby is also worth using. The Main Stacks in Doe can be v. silent, particularly is you're able to get a carrel of sorts.