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In this lecture Quantum Mechanics in your face by Sidney Coleman

http://www.youtube.com/watch?v=EtyNMlXN-sw

Does he state that there's only evolution according to Schrodinger's equation in QM and it is basically deterministic? (at around 45 minutes)

Qmechanic
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Viesr
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    I'm voting to close this question as off-topic because it's about what Sidney Coleman said not about physics – John Rennie Nov 26 '15 at 06:13
  • Yes, Coleman does say that. Coleman is essentially describing the many worlds interpretation of QM. Incidentally this is an excellent lecture and I strongly recommend it to amateur physicists - experienced physicists will find it rather basic though quite fun. – John Rennie Nov 26 '15 at 06:30
  • @JohnRennie Yes, but isn't that wrong? I mean it simply can't be evolution according to schrodinger's equation. – Viesr Nov 27 '15 at 06:39
  • Why not? My own view is along the same lines as Coleman's. I believe the wavefunction collapse is due to something like a many worlds idea. – John Rennie Nov 27 '15 at 06:40
  • @JohnRennie Suppose there is a particle in a superposition of spin up and down, and I subject it to a macroscopic magnetic potential. Then since Schrodinger's equation is deterministic. Hence, it must give one answer in this situation for evolution of wave function, but this isn't what we see in experiment. – Viesr Nov 27 '15 at 10:46
  • You've missed the message in Coleman's talk. Anything that interacts with the superposed state becomes entangled with it and also becomes a superposed state. This far everything evolves according to Schrodinger's equation. The Copenhagen interpretation version of wavefunction collapse is not described by Schrodinger's equation, but the Many Worlds interpretation is that there is no collapse and therefore the system always evolves according to the Schrodinger equation. – John Rennie Nov 27 '15 at 10:50
  • @JohnRennie I was thinking so. I've missed the message from his lecture. Can you please explain what you're saying in terms of the spin experiment I mentioned in my previous comment. It'd be really helpful. – Viesr Nov 27 '15 at 11:05
  • You need to go and read up about the many worlds interpretation. Feel free to come back to us and ask a new question if you need any aspects of the many worlds ideas clarifying. You might want to start with Timaeus' answer to this question. – John Rennie Nov 27 '15 at 11:10
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    @JohnRennie This splitting of waves he's talking about. I don't understand how it explains seeing one particular result taking place for sending just one electron through the Stern Gerlach experiment. He just explains this upto the point that two outcomes are possible. – Viesr Nov 27 '15 at 17:34

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