Atom Wave Function: Definition & Explained

[gabrielh]

Below is an excerpt from Quantum Enigma: Physics Encounters Consciousness. I have a few questions following the text.

Any wave can be reflected. A semitransparent mirror reflects part of a wave and allows the rest to go through. A glass windowpane, for example, allows some light through and reflects some. A semitransparent mirror for light is a semitransparent mirror for photons. The wavefunction of each individual photon hitting a semitransparent mirror splits, with part being reflected and part transmitted. We can also have semitransparent mirrors for atoms. Encountering such a mirror, an atom's wavefunction splits into two wave packets; one packet goes through, and another is reflected.

Holding an atom in a box pair without disturbing its wavefunction would be tricky, but possible. Dividing the wavefunction of an atom into two well separated regions is frequently accomplished, and that's all we really need for our story. Quantum theory says the atoms "waviness", and therefore the atom itself, is simultaneously in both boxes.

The text goes on to describe that by opening holes in the boxes, the wave function leaks out of both boxes and falls on a screen to which an atom will stick, resulting in an interference pattern. Another option would be to simply open one of these boxes to see which box contained the atom. The act of choosing which experiment to do yielded the results you would expect for that experiment.

I'm looking for a better definition of what the wavefunction is and if it is indeed a physical thing. Also, any simplified explanations of the quoted text is welcomed too.

 

[DrClaude]

I'm looking for a better definition of what the wavefunction is and if it is indeed a physical thing. Also, any simplified explanations of the quoted text is welcomed too.

To understand what the wave function is, you'll have to crack open a textbook on quantum mechanics.

Whether the wave function is a physical thing or not is an unresolved question. See for insatnce
https://www.physicsforums.com/threads/ontology-of-wavefunction-vs-ontology-of-electric-field.884957/
To understand what the quoted text means, see
https://en.wikipedia.org/wiki/Atom_interferometer