Quantum Mechanics, Schrodinger equations and energy eigenvalues

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To find energy eigenvalues from the Time Independent Schrödinger Equation (TISE) for a given potential, one typically solves the differential equation associated with the potential. If the wavefunction is an eigenfunction of the Hamiltonian, substituting it back into the TISE allows for the extraction of energy values. For specific potentials like the harmonic oscillator, alternative methods such as the ladder operator technique can be employed, which simplifies the process without needing to find the wavefunctions explicitly. The expression E = (N + 1) ħω arises from these methods, indicating quantized energy levels. Understanding the relationship between the potential and the resulting eigenvalues is crucial in quantum mechanics.
Badger01
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How do you find an expression for the energy eigenvalues from the TISE (Time Indipendant Schrodinger Equation) for a given potential.

e.g. why is:
E = (N + 1) hbar*omega
an expression for the energy eigenvalues for a potential of:
V = 1/2*m*omega2x2
??

I really have no idea where to start with this.

thanks for any help
(sorry about the lack of simbols, i couldn't get them to work)
for a better setup see
http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/scheq.html
the section on energy eigenvalues
 
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Badger01 said:
How do you find an expression for the energy eigenvalues from the TISE (Time Indipendant Schrodinger Equation) for a given potential.

e.g. why is:
E = (N + 1) hbar*omega
an expression for the energy eigenvalues for a potential of:
V = 1/2*m*omega2x2
??

I really have no idea where to start with this.

thanks for any help
(sorry about the lack of simbols, i couldn't get them to work)
for a better setup see
http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/scheq.html
the section on energy eigenvalues

There is not a straightforward method for cleanly determining the energy eigenvalues for an arbitrary potential, because not every arbitrary potential results in a TISE that has a closed-form solution. The most general way to go about it, though, is simply to solve the differential equation (if you can). Once you have the wavefunction(s) that solves the TISE, you then substitute it back into the TISE and evaluate the Hamiltonian acting on the wavefunction. If it is an eigenfunction of the Hamiltonian, the left side of H \psi = E \psi turns into some number times ψ, so the wave-function cancels out and you're left with the energy.

But there are often other methods for determining the energy levels without explicitly finding the wave-functions. In the case of the harmonic oscillator potential, that would be the ladder operator method. It's in pretty much any introductory level QM book (e.g. Griffiths).
 
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