Undergrad Find the energy from the graph of the wave function

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It is possible to determine the kinetic and potential energy of a quantum system from the graph of its wave function, specifically an eigenfunction of the Hamiltonian. The second derivative of the wave function corresponds to the kinetic energy operator, represented as -ħ²/2m ∇². Eigenfunctions of the Hamiltonian yield eigenvalues that represent the total energy, which is the sum of kinetic and potential energy. To isolate potential energy, both the second spatial derivative and the time derivative of the wave function are necessary. Understanding these relationships is crucial for analyzing quantum systems effectively.
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##
 
Time reversal invariant Hamiltonians must satisfy ##[H,\Theta]=0## where ##\Theta## is time reversal operator. However, in some texts (for example see Many-body Quantum Theory in Condensed Matter Physics an introduction, HENRIK BRUUS and KARSTEN FLENSBERG, Corrected version: 14 January 2016, section 7.1.4) the time reversal invariant condition is introduced as ##H=H^*##. How these two conditions are identical?

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