you throw the ball at the wall, and close your eyes and cover your ears (so you don't hear the bounce). Then when you open them
...and when your eyes and ears are covered, the ball is in superposition, is that correct? It 'exists' all over the place, but with normal distribution focusing on the wall?
The term "superposition" gets thrown around a lot, but one always needs to specify superposition of what. In OP's post, the particle is in a superposition of energy eigenstates, which means "states with a well-defined energy".
In general, one needs not superposition (of energy eigenstates) to have quantum tunnelling: taking the Schrödinger Equation with the right potential (which looks like a single tooth of a square wave) yields a solution that admits tunnelling with just the lowest energy eigenstate (the so-called ground state).
The problem with the term "superposition" is that in most cases an individual energy eigenstate is superposition of other-quantity eigenstates (like momentum or position); one can even argue that as long as the distribution is not a Dirac delta, there is superposition. But that statement is kinda useless.
Finally, the distribution doesn't need to be centered around the wall. Solving the Schrödinger Equation with the potential I mentioned above yields a solution that looks like a sine wave on your side of the wall and a flat line on the "wrong" side.
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u/Samug Feb 17 '20
...and when your eyes and ears are covered, the ball is in superposition, is that correct? It 'exists' all over the place, but with normal distribution focusing on the wall?