I Postulate of only time dependence on |ψ⟩

LightPhoton
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Answers to questions like this assume that the quantum state in a Hilbert space is only a function of time, that is ##\partial_i\vert\psi(t)\rangle\neq0## only when the variable ##i## is ##t##.

Is this a postulate of standard quantum mechanics, that in Schrödinger's equation the state in abstract only depends on time?
 
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LightPhoton said:
Is this a postulate of standard quantum mechanics, that in Schrödinger's equation the state in abstract only depends on time?
What else could it depend on? What else could anything depend on?
 
PeroK said:
What else could it depend on? What else could anything depend on?
To explain what I mean by this. Let's take some function ##E##, say, that describes the global socio-political-economic state. That state will change over time: ##E(t)##. What else could it be a function of? Everything else is bundled into that function - population, political and economic policies etc.

The state tells you everything about a system at a point in time. The only free variable, if I can use that term, is time. You may be able to analyse the state at a point in time in many ways. But, if the state itself is complete, then time evolution is the only remaining variable.
 
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