Electrons fired through a double slit one at a time still build up interference fringes on the screen, given enough of them: each particle went through both slits in the wave sense. The same set of rules shapes the s, p and d orbitals, lets particles tunnel through barriers, produces entangled pairs, and sets a floor on every measurement through the uncertainty principle. What collapses a wavefunction to a single outcome is a physical interaction with the apparatus, not an observer paying attention.
Electrons fired through a double slit one at a time still build up interference fringes on the screen, given enough of them: each particle went through both slits in the wave sense. The same set of rules shapes the s, p and d orbitals, lets particles tunnel through barriers, produces entangled pairs, and sets a floor on every measurement through the uncertainty principle. What collapses a wavefunction to a single outcome is a physical interaction with the apparatus, not an observer paying attention.
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