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