1. The problem statement, all variables and given/known data Hello, I'm just curious as to whether I'm going about solving the following problem correctly... Problem Statement: A particle mass m and charge q is in the ground state of a one -dimensional harmonic oscillator, the oscillator frequency is ω_o. An electric field ε_o is suddenly turned on. Show that immediately afterwards the probability the particle is in the new ground state is given by exp(-q^2ε_o^2/2mω_o^3) 3. The attempt at a solution I know I have to take the inner product of the old wavefunction with the new wavefunction, and I know that the new potential of the harmonic oscillator is going to be given by H = p^2/(2m) + (1/2)mw^2x^2 - ekx where V = -integral(E) = -kx So my question is how does the wavefunction change and why? and also my teacher hinted that we would have to complete the square and I don't see any equations that require completing the square in my attempt at a solution so I'm know something is horribly wrong... Any help would be appreciated :) thanks!