I was just wondering what courses in applied mathematics are needed for physics.
I imagine any branch of physics will make heavy use of calculus and differential equations, and probably linear algebra. What kinds of mathematics you'll be utilizing depends on what you're studying, but the happy/sad news is that the more math you know the better.
The standard assumption is Linear Algebra, a complete Calculus sequence (including multivarate), and Differential Equations.
From what I have actually seen in my upper division course load taking courses on the following math subjects are also useful:
Differential Geometry, Tensor Anaylisis, Complex Anaylisis/Boundry Value Problems, Calculus of Variations, a course on Waves/Oscillations from a math department (if offered), and an applied group theory course.
A few stats courses, like ones designed for science and engineering majors and/or some numerical methods courses (my math department splits them between math and stats pretty evenly, so I don't know where one would like to place it).
However, as I said before the first list is likely the only required mathematics course work in physics, the rest are just good subjects to pick up on the way.
I'd also recommend a course in fractal geometry in addition to those above.
from my experience as an undergrad, it seems like you can get by at the undergraduate level with just your calc sequence, elementary differential equations, and linear algebra. taking courses on complex variables and numerical analysis might be a good idea, too.
(some graduate level courses in physics seem to assume some experience with contour integrals--in the grad qm class i took last fall, we needed to either recall or look up the integral of sinx/x from -infinity to +infinity. the numerical analysis class i took didn't have useful material, per se, but it helped me solidify my scientific computing skills.)
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