Question

The variational method can be used to solve for the ground state wavefunction and energy of a harmonic oscillator. Using a trail wavefunction of coS , where the function is defined between -\pi /2\lambda < x< \pi /2\lambda . The Hamiltonian operator for a 1D harmonic oscillator is H = -h/4\pi \mu *d^2/dx^2+kx^2/2 Solving for the wavefunction gives E(\lambda )=h^2\lambda ^2/4\pi \mu +0.161k/\lambda ^2

Find \lambda that gives the lowest energy and compare from the trial function to the exact value, E_{0}=h\omega /4\pi where \omega=\sqrt{(k/\mu )}

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41卜 3 0.322 k IT 4 12 4IT 47T

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The variational method can be used to solve for the ground state wavefunction and energy of a harmonic oscillator. Using a trail wavefunction of , where the function is defined between . The Hamilto...
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