Find the energy from the graph of the wave function

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HastiM
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Hello,

I am wondering if it is possible to determine the kinetic energy and potential energy of a quantum system just by investigating the graph of its wave function. Suppose we are given the graph of some wave function Ψ(x), i.e. a function which is an eigenfunction of the hamiltonian. I think its second derivative Ψ''(x) should somehow correspond to the kinetic energy of the particle. Is that right? What about the potential energy?

Best regards
 
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Yes, ##\displaystyle {-{\hbar^2\over 2m}\nabla^2} ## is the kinetic energy operator.

Eigenfunctions of the Hamiltonian have eigenvalues corresponding to the total energy ##T+V## .

So, only if you have the second spatial derivative and the time derivative can you deduct ##V##