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Particle collisions collapse wave function?

  1. Jul 22, 2009 #1
    I am imagining the collision between two subatomic particles. For the particles to have collided, do we say that the spatial wave functions for each particle must have collapsed to the same point? Or do we say that the particles are just in a very close vicinity, and the wave functions need not have collapsed completely (i.e., to the delta function)? References or further reading would be appreciated.
  2. jcsd
  3. Jul 23, 2009 #2
    Maybe I should phrase this a little differently. I am just interested in how particle collisions are dealt with in physics. Since particles have probability distributions, I am confused as to how we represent the collision. Classically, when two objects (say two baseballs) collide they are actually touching each other at some point. But in atomic physics, obviously the particles are not precisely localized, so this interpretation wouldn't make sense. It might make sense if you assume that the particles' probability distributions have "collapsed" to the same point. However, I can imagine that a particle "collision" simply refers to an interaction between their wave functions, not an actual classical bumping together sort of thing.
  4. Jul 23, 2009 #3
    Scattering theory is VERY complicated but in the simplest situation we simply consider and incident wavefunction (of the form exp(-ikz) andthen a scattered wavefunction (which is more complicated) and often view it as interacting with a potential function V(r) in the collision reference frame (I can't remember what it's called, center of momentum frame maybe). But not, scattering events do not collapse wavefunctions.
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