Suppose that I have a single massive quantum mechanical particle in d dimensions (1≤d≤3), under the action of a well-behaved potential V(r), and that I let it settle on the ground state |ψ0⟩ of its hamiltonian, [p22m+V(r)]|ψ0⟩=E0|ψ0⟩.
This wavefunction can be examined in phase space in a number of ways, such as using Wigner functions or the Sudarshan P and Husimi Q representations, all of which offer different views into the state and different quasi-classical ways to understand it. My precise question is as follows:
- Is there a way to translate wavefunctions |ψ⟩ of a quantum system into probability distributions ρ(r,p) over classical phase space, in such a way that the eigenstates of a given quantum hamiltonian will be stationary states of the Liouville equation for the corresponding classical system?
To be fully explicit, I want a map such that produces a classical density with the correct position and momentum distributions, i.e. ∫ρ(r,p)dp=|⟨r|ψ⟩|2 and ∫ρ(r,p)dr=|⟨p|ψ⟩|2, and ideally also for all possible quadratures at any angle. The classical ρ(r,p) should remain stationary under Liouville's equation with a classical hamiltonian H(r,p) that connects to the quantum hamiltonian via a classical limit or canonical quantization, in the general case, but I'm happy to restrict this to hamiltonians of the form H(r,p)=p22m+V(r), in which the correspondence is obvious.
More intuitively, I know that after the translation I will get a counterfeit ρ(r,p) that doesn't actually describe what's going on, but at least I would like it to sit still once I let classical mechanics take over.
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