Hi fellow math friends,

as April 15th is only about a day away, i am in need of some serious help. (edit: I am aware that this is very last minute, but I got back from the visits last night so I couldn't make a decision until this weekend (got admitted to USC a couple nights ago)). I am trying to decide between University of Minnesota and University of Southern California. I am interested in geometric combinatorics and low-dimensinal topology (knot theory) (although I keep an open mind about these interests.. could change later). U of M is an extremely great school for combinatorics and there are quite a few people (who are well-known in their field) I would like to work with; on the other hand, USC also has a great, reputable advisor (Francis Bonahon) who said he'd be willing to work with me in knot theory, and there is another person in combinatorics who I'd like to work with as well (when I talked to her, she told me U of M would be a great school for combinatorics). I have visited both schools and I loved both of them. I am so confused as to which school I should pick. If I went to USC, I would only have two options for advisors, one in each of my areas of interest. If I went to U of M, I think I'd mostly likely be doing combinatorics, with plenty options for an advisor, but I'm not sure If I'd have any options for knot theory.

So far I've been leaning towards U of M, because it had more of a friendly, homey vibe that I really adored when I visited. And I really liked the combinatorics group there. I got along great with everyone there, and the whole program is just so supportive and there's a cooperative friendly atmosphere. As with USC, despite their lower ranking, they've been doing a great job at placing students with jobs (haha) as well, and I shouldn't have any problem getting a job if I work with Bonahon. Also I am afraid that I might change my mind about combinatorics later. And, although this isn't a deciding factor, weather in southern california is just too gorgeous and USC's campus is just stunning. USC has offered me a bit more money, about $3000 more, but considering it's LA it's not that significant of a difference.

What should I do? I am in need of some outside opinions. Please help!! Any feedback would be appreciated!