I am about a year into an undergraduate degree in Physics and I am wondering what might lay ahead. What do the more experienced mathematicians think is the most difficult subject? a couple things happended recently that made me ponder the subject. - My calc2 professor was lecturing on applicaitons of the deginate integral, specifically in regard to the work function. In doing so, he admitted to the class that this was his least favorite lecture becuase he was not as comfortable with the Physics. I thought it was an odd coment becuase he seems like the most intelligent professor I have ever had. W=Fd is so simple, how could that seem difficult to a guy that knows all the ins and out of calculus? - I was reading an interview of a Mathematic PHD. He was asked what he thought was the most difficult mathematics. "Definetly Advanced Calculus" was his reply. I had always just assumed the math gets more and more difficult as you progress. I may be showing how green I am, but what is 'Advanced Calculus'? Is that Calc 3? Or, are there more higher level calculus classes? If calc3 is as hard as it gets, that does not seem too difficult. Honestly, I really enjoy calculus -when you really get to apply it, as in optimization and applications of the definate integral. They just make a lot of sence. I enjoy them because it is like writing an essay, except in the most efficiant of language. I like applying the concepts of calculus, rate of change and the limit of summations. You can spend all this time in math playing logic games, but what is the point unless you can use it to tell you something about the world. I'll work all day trying to figure out a problem if the answer will actually tell me something interesting like how much work is required to move an object. It is the nitty gritty algebra at the end that always causes me trouble. Algebra is what I would consider the most difficult. My physics professor is always setting up problems for us, and then saying "the rest is just algebra, and if you cant do that, you should not be in this class" Which is true, no doubt, but I dont like the implication that it is "just algebra". Algebra can be a major in pain in the arse. Anyway, just curious, what someone with more experience might think.