Most Likely Position of an Electron

[vanhees71]

My point is that they don't commute with the variables you have already specified. Maybe that was unclear.

And while you can calculate what the probability was, you cant calculate what it is. "The electron is in a 1S state" and "the electron is over here" (or even "not over here") are incompatible.

Sigh. Of course you can, in principle, ask about the position of an electron in the 1S state of a hydrogen atom. Nothing forbids to measure observables of a system only because the system is not in an eigenstate of the measured observable. It's only that due to the preparation in this state the position is indetermined, and you'll find a probability density when repeating the same measurement on many electrons prepared in this 1S state.