I have to admit that I don't know much about String Theory (or QFT, for that matter ..), but, if we assume that String Theory is the correct description of fundamental particles, what is the correct way to think about a wavefunction, in the context of String Theory?
For example, take an electron being shot from an emitter to a target. I usually imagine the wavefunction as spreading out from the target in three dimensions, possibly traveling through two or more slits; interfering with itself along the way; and then spontaneously deciding to collapse down onto one of the atoms that makes up the target surface. Where does the string fit into this picture?
Does String Theory say anything about the mysterious wavefunction collapse? (I assume it must do, otherwise can it really be described as a 'theory of everything'?)
It was mentioned in one of the answers that, in string theory, 'point particles' are described as strings. Hang on though .. in QM we were told: "there are no point particles, there are only wavefunctions." But, now in string theory, apparently these point particles are back again, only they're now described as strings. So, where did the wavefunctions go?