math vs physics undergrad?(then PhD)

<p>Haha, the OP here is like my clone; I love physics and philosophy too: <a href="http://talk.collegeconfidential.com/showthread.php?t=69369&highlight=choosing+major%5B/url%5D"&gt;http://talk.collegeconfidential.com/showthread.php?t=69369&highlight=choosing+major&lt;/a&gt;&lt;/p>

<p>But I think I've decided to major in simply physics, and take other courses that interest me. Could you guys answer a couple of questions for me, though? I will probably be attending UMCP for the first couple of years, and I want to know what goals I should be aiming for. I either want to transfer to or attend grad school at a top physics university (MIT/Caltech). So I wonder: What are reasonable GPA's for a transfer and a grad school applicants in physics? And when should I begin doing research? Do I need a substancial amount of physics knowledge before profs will even consider working with me? I am seriously willing to work my ass off here--I really love this subject, and I want to show it. I lost my chance at high school, and I don't want to lose it again (..although I have no problem with UMCP).</p>

<p>I'm also curious about getting a physics PhD, in theory, if possible.
Does this present an added complication?</p>