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### Can Newton's laws be explained by Quantum Physics? [duplicate]

I have only basic knowledge of physics. Could you please explain to me if a "Quantum" laws can theoretically (perhaps in the future?) be used to explain everything in macro levels? I'm having ...
2k views

### From Quantum Mechanics to Classical Mechanics [duplicate]

Is it possible, and has it been attempted, to use quantum mechanics to deduce Newtonian, macroscopic level mechanics laws as was the case of statistical mechanics deriving thermodynamic relations?
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### Can the laws of classical mechanics be derived from quantum mechanics? [duplicate]

Can classical mechanics be derived from quantum mechanics as the same way thermodynamics derived from statistical mechanics?
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### How to prove Newton's second law with quantum mechanics? [duplicate]

Newton's second law claims that $F=ma$. In terms of quantum mechanics, the equality can be written as $\frac{d\langle p \rangle}{dt} = -\langle \nabla V(x) \rangle$. How can I prove this with non-...
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### How to go from Quantum World to Classical World? [duplicate]

Possible Duplicate: Is it possible to recover Classical Mechanics from Schrödinger’s equation? Classical Limit of the Feynman Path Integral In the quantum world we don't have specific ...
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### Classical limit of quantum mechanics

I have heard that one can recover classical mechanics from quantum mechanics in the limit the $\hbar$ goes to zero. How can this be done? (Ideally, I would love to see something like: as $\hbar$ ...
Let's take the very simple problem of what happens if I drop a 1 kg ball from a height of 1 meter. Classically, $F = mg$ and $g \approx 10 \frac{\mathrm{m}}{\mathrm{s}^2}$, so the ball feels a force ...