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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Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!
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