I have read this:
It says that elastic scattering creates cylindrical waves, and that creates interference pattern, and the constructive interference will create the bright parts visible on the screen.
It says that inelastic scattering creates spherical waves, and that does not create interference, at least not constructive interference, that would be visible as bright pattern on the screen.
I did not find anything on why the spatial shape of the wave would hinder it from creating an interference.
In this double slit experiment, the cylindrical waves (elastic scattering in air), the ones that go through a slit without any filter, will create visible bright interference pattern.
Now in this experiment, the photons or electrons are shot one at a time, still they create interference, because they travel as waves and the partial waves that go through the slits interfere with each other.
But why does it matter what spatial shape the waves have, shouldn't both type of shape of waves go through the slits and interfere and create an interference pattern? We are talking about single electrons or photons shot at a time. Even a single particle should create an interference pattern, and it should not matter what spatial shape the partial waves have.
Is there and explanation why cylindrical waves create an interference pattern, and why spherical waves do not?
Why does the spatial shape of a wave matter in interference?