Find the transition probability

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tgr042
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Applying an operator
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to an initial state
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can cause it to change into a different state
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, if
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is not an eigenstate of
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. The probability for this transition to occur is
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, where
Integral expression A = integral from negative infinity to infinity of psi_f*(x) T-hat psi_i(x) dx, the transition amplitude between two states.
is called the transition amplitude. Consider the case where the initial state is the
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state of the harmonic oscillator,
Handwritten equation: psi_i(x) = psi_2^(HO)(x), where psi_i is the initial state and psi_2^(HO) is the second harmonic oscillator eigenstate.
, the final state is the
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state of the harmonic oscillator,
Equation: psi_f(x) = psi_3^(HO)(x), where psi_f is the final state wavefunction set equal to the third harmonic oscillator eigenstate.
, and the operator is
Handwritten expression T̂ = x̂³, with a hat over T and over x.
. (
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is the position operator.) Find the transition probability from
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to
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.I really am not even sure where to start...
 
Look up the eigenfunctions of the harmonic oscillator, operate with the given operator on the initial state, integrate according to the definition of the transition amplitude.
 
When you say on the initial state do you mean when psi(n)=1/sqrt(n) a+ psi(n-1) or do you mean psi(2)=1/sqrt(2) a+ psi(1)