zlacker

>>qqqqqu+(OP)
Why does quantum mechanics need complex numbers ?

Every time I read an introductory QM book / article, the complex numbers just come out of nowhere and no one bothers to explain how that makes any kind of physical sense.

>>ur-wha+Nb1
Imaginary numbers, pretty much everywhere in physics, represent an extra dimension. e^ix results in a unit vector spinning around.

>>OkayPh+Ev1
Thanks for your answer, but that doesn't really cut it for me. For example, if complex numbers are so "natural" at modeling rotations, why don't they show up e.g. in Maxwell's equations ?