There is something I never understood in the double slit. Here is a picture. http://www.physics.colostate.edu/users/pavol/anims/physics/double_slit.gif [Broken] When the particle is emitted from a source, if it truly acts like a wave, then wouldn't it sometimes hit the wall in-between the slits? And, wouldn't this cause the wave function to collapse? Please help me understand. Thanks in advance.