1. The problem statement, all variables and given/known data This isn't a homework problem, just something I've been trying to conceptualize for a while. Can anyone exemplify with a physical analog the concept of eigenstates? For example, I know that eigenvalues of variables with continuous spectra do not exist in the physical hilbert space, but I really can't get a working grasp of that concept. This would really help to solidify QM for me if someone can explain this, thanks.