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Quantum mechanics doesn't provide "positive evidence that reality is contextual and non-concrete." 1) A quantum state can exist in a superposition of different

Quantum mechanics doesn't provide "positive evidence that reality is contextual and non-concrete." 1) A quantum state can exist in a superposition of different states, but once measured, it collapses into one and only one state. If measured again it will still be in that state. So it is "concrete" in that sense. 2) "Contextual" is a word usually used to describe language, not physical measurements. However, if you mean that the state of a system depends on the state of every other system around it, then that, too, is not correct. Special relativity and the speed-of-light speed limit place hard constraints on what can affect an event at a specified time and place.

Kednicma 6y ago
Recall that "ontic" and "epistemic" are how we distinguish real facts about reality from observer-dependent knowledge about reality. On your (1), the typical interpretations for QM say that the wavefunction is not ontic, and this is directly traceable to the Copenhagen school of thought. QM is best done when we consider that our knowledge of systems is always partial; it turns out that often, the system itself is also partial about knowledge of own state. I greatly enjoyed reading [0] recently for a coverage of a toy theory exploring this distinction in more detail. On your (2), quantum contextuality [1] means something more subtle than your phrasing; it means that the state of a system is not the entirety of what is measured by an observer. To use your phrasing and state something very strong, the Free Will Theorem [2] says that the state of a system informs, but can never totally control, the way that a particle chooses to reply to an observer taking a measurement. This both opens the door for new avenues in free-will philosophy while slamming shut the idea that e.g. determinism can be meaningful or possible. [0] https://arxiv.org/abs/quant-ph/0401052 https://arxiv.org/abs/quant-ph/0401052 [1] https://en.wikipedia.org/wiki/Quantum_contextuality https://en.wikipedia.org/wiki/Quantum_contextuality [2] https://en.wikipedia.org/wiki/Free_will_theorem https://en.wikipedia.org/wiki/Free_will_theorem
- noslenwerdna 6y ago
  Thanks for your thoughtful response. I must say [0] does look interesting, though I've only glanced over it. I would just point out that, a) it's not observer dependent, it's measurement dependent. If you collapse a wave-function in a superposition of states into state A, when I measure it, it will be state A as well. In that sense it is very concrete. b) surely you can see my confusion at your statement on contextual vs. quantum contextuality. For latter is a technical term, but the former was used in a non-technical way.

Kednicma 6y ago

Recall that "ontic" and "epistemic" are how we distinguish real facts about reality from observer-dependent knowledge about reality. On your (1), the typical interpretations for QM say that the wavefunction is not ontic, and this is directly traceable to the Copenhagen school of thought. QM is best done when we consider that our knowledge of systems is always partial; it turns out that often, the system itself is also partial about knowledge of own state. I greatly enjoyed reading [0] recently for a coverage of a toy theory exploring this distinction in more detail. On your (2), quantum contextuality [1] means something more subtle than your phrasing; it means that the state of a system is not the entirety of what is measured by an observer. To use your phrasing and state something very strong, the Free Will Theorem [2] says that the state of a system informs, but can never totally control, the way that a particle chooses to reply to an observer taking a measurement. This both opens the door for new avenues in free-will philosophy while slamming shut the idea that e.g. determinism can be meaningful or possible. [0] https://arxiv.org/abs/quant-ph/0401052 https://arxiv.org/abs/quant-ph/0401052 [1] https://en.wikipedia.org/wiki/Quantum_contextuality https://en.wikipedia.org/wiki/Quantum_contextuality [2] https://en.wikipedia.org/wiki/Free_will_theorem https://en.wikipedia.org/wiki/Free_will_theorem

noslenwerdna 6y ago
Thanks for your thoughtful response. I must say [0] does look interesting, though I've only glanced over it. I would just point out that, a) it's not observer dependent, it's measurement dependent. If you collapse a wave-function in a superposition of states into state A, when I measure it, it will be state A as well. In that sense it is very concrete. b) surely you can see my confusion at your statement on contextual vs. quantum contextuality. For latter is a technical term, but the former was used in a non-technical way.