I have a wave function which is the ground state of a harmonic oscillator (potential centered at x=0)... but shifted by a constant along the position axis (ie. (x-b) instead of x in the exponential). How does this decompose into eigenfunctions?!?! I know it's an infinite sum... but I can't nail the coefficients. ...and... without knowing the decomposition, how can I get the time development of the average position and momentum??? Help. Thanks.