Apologize if this is a dumb question, I'm just a kid trying to make sense of something that I'm new to.
It shows the wave interference when you send a classical wave through in the second example, where two essentially "new" waves are created at the beginning of each slit at the same time, so adding them together results in the classic two slit pattern. But at the same time, when they send a quantum object through with an observer, the wavefunction collapses and the particle only goes through one slit - but then a new probability wave forms past the observer on the other side of the slit, and as expected the particle's final location follows this probability wave.
My question is, why doesn't interference occur with the observer here? Aren't there still probability waves between the quantum objects going through each slit, and shouldn't these waves interfere and create fringes of some sort?