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It is the root of quantum mechanics that Heisenberg picture and Schrödinger picture are equivalent?

In most textbooks and wikipedia, the equivalence is proved with a time-independent Hamiltonian. However, some literature uses Heisenberg equation with time-dependent Hamiltonian.

$$i\hbar \frac{dA}{dt}~=~[A(t),H(t)]+i\hbar \frac{\partial A}{\partial t}.$$

So, does Heisenberg equation work with time-dependent Hamiltonian? If so, any proof?

Qmechanic
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atbug
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  • Related: https://physics.stackexchange.com/q/11264/2451 , https://physics.stackexchange.com/q/122687/2451 , https://physics.stackexchange.com/q/5236/2451 and links therein. – Qmechanic Nov 17 '16 at 06:49

2 Answers2

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The short answer is that the time evolution operator for a time-dependent Hamiltonian has two times, the initial and final $U (t,s) $.

Therefore defining $A (t,s)=U (s,t)A U (t,s) $, the Heisenberg equation is obtained differentiating with respect to $t $. Schroedinger equation is obtained differentiating $U (t,s) \psi (s)$ instead. The two are equivalent in the usual sense, i.e. they both give the same time-evolved transition amplitudes.

yuggib
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OK, I figured it out myself. Heisenberg equation still holds for time-dependent Hamiltonians:

$$i\hbar \frac{dA}{dt}~=~[A(t),H(t)]+i\hbar \frac{\partial A}{\partial t}.$$

However, now $H(t)$ is defined as $U^\dagger(t)H_S(t)U(t)$.

atbug
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