What is Hidden variables: Definition and 62 Discussions

In physics, hidden-variable theories are proposals to provide explanations of quantum mechanical phenomena through the introduction of unobservable hypothetical entities. The existence of fundamental indeterminacy for some measurements is assumed as part of the mathematical formulation of quantum mechanics; moreover, bounds for indeterminacy can be expressed in a quantitative form by the Heisenberg uncertainty principle. Most hidden-variable theories are attempts at a deterministic description of quantum mechanics, to avoid quantum indeterminacy, but at the expense of requiring the existence of nonlocal interactions.
Albert Einstein objected to the fundamentally probabilistic nature of quantum mechanics, and famously declared "I am convinced God does not play dice". Einstein, Podolsky, and Rosen argued that quantum mechanics is an incomplete description of reality. Bell's theorem would later suggest that local hidden variables (a way for finding a complete description of reality) of certain types are impossible.
A famous non-local theory is the De Broglie–Bohm theory.

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  1. Lynch101

    I Looking For Help Understanding Bell's Theorem, Hidden Variables & QM

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  2. PainterGuy

    B Quantum entanglement and hidden variables

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  3. DrChinese

    A How Many Hidden Variables Would It Take to Model Photon Polarization?

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  4. P

    B Is an experiment planned to discern determinism and randomness in QM

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  5. BWV

    I How do hidden variables supposedly explain radioactive decay?

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  6. J

    I Is completeness synonymous with hidden variables in QM?

    In one of the Insights. Either QM is incomplete (because we only have access to probabilities in conventional experiment) or there are Many Worlds. I want to pick incompleteness. But in Einstein context of it. Incompleteness means there were hidden variables. Is there another meaning of...
  7. Quantum Entanglement: Spooky Action at a Distance

    Quantum Entanglement: Spooky Action at a Distance

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  8. H

    I Do Hidden Variables include sub-structures?

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  9. J

    I Relational Hidden Variables (Real ensemble or thermal?)

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  10. P

    A No hidden variables in QM - a paradigm shift?

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  11. A

    A Does Bell's theorem imply nonlocality using a false assumption

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  12. J

    A Are Modal interpretations emprically Lorentz invariant?

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  13. DarMM

    A Non-Computability of Hidden Variables

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  14. A. Neumaier

    I Relativistic hidden variable quantum mechanics?

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  15. B

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  16. R

    B A question about Bell's Inequality and hidden variables

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  17. The_Inventor

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  18. F

    I Could Hidden Variables Explain Quantum Mechanics without Locality?

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  19. S

    I Why isn't tunnelling considered proof of hidden variables?

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  20. Jilang

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  21. G

    B Other terms for indeterministic hidden variables

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  22. G

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  23. G

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  24. naima

    A What should hidden variables explain?

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  25. A

    Is BI really required to validate the Hidden Variables?

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  26. entropy1

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  27. morrobay

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  28. Jimster41

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  29. atyy

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  30. G

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  31. atyy

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  32. L

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  33. G

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  34. stevendaryl

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  35. B

    Could the hidden variables be encoded in the observer?

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  36. Zafa Pi

    Hidden variables - Bell - The Law of Malus?

    Invariably in the lay literature when it comes time to show that EPR hidden variables are incompatible with QM, Bell's Theorem is invoked (e.g. Greene's "Fabric of the Cosmos", Zeilinger's "Dance of the Photons", Rosenblum's "Quantum Enigma", ...). I don't see why a simple application of...
  37. M

    Bell Proof Against Hidden Variables in EPR

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  38. D

    Everyday analogy why hidden variables can’t explain entanglement

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  39. H

    Some thoughts on the hidden variables interpertation

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  40. S

    Understanding bell's theorem: why hidden variables imply a linear relationship?

    (Part of) The proof/logic of Bell's theorem goes thus: With the measurements oriented at intermediate angles between these basic cases, the existence of local hidden variables would imply a linear variation in the correlation. However, according to quantum mechanical theory, the correlation...
  41. G

    Bell's Experiments & Hidden Variables

    Hello everyone, I was reading about Bell's theorem on Wikipedia. One thing I found particularly interesting: In particular number 2. The points he made can be found at http://bayes.wustl.edu/etj/articles/cmystery.pdf . While I did not understand all the steps from Bell's Theorem, I think...
  42. Demystifier

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  43. E

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  44. Demystifier

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  45. M

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  46. K

    Is non-linearity incontrovertible? What about hidden variables?

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  47. A

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  48. inflector

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  49. D

    Hidden variables, Bell's theorem, etc

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  50. maverick_starstrider

    Yes, that helps clarify things. Thank you for the explanation.

    Is there a non-local hidden variable theory that accounts for things like BEC's? Did Bahm's original one? Thanks in advance.
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