Bell's theorem is popularly stated as the inconsistency of quantum theory with local realism. Realism is here formalized by the ontological models framework, where elements of reality are points of a measurable space and probabilities obey the Kolmogorov axioms. In the Bell scenario, locally causal ontological models posit a common cause supporting a global valuation, a joint assignment of outcomes to all measurements at once, across incompatible contexts. Within this notion of realism, Bell's theorem makes any realist explanation of the quantum predictions conspiratorial: any mechanism, whether superluminal, superdeterministic, or retrocausal, must be finely tuned so as never to manifest operationally. We redefine realism through a new ontological framework that generalizes the standard one. The elements of reality, which we call records, are no longer points but relational parts of a point-free generalization of a topological space (sublocales of a locale). A record shared by two incompatible contexts establishes the sameness of a measurement across them, without such pairwise identities composing into a global valuation, and the common cause is then a web of such records. Within this framework, Bell's no-go theorem becomes a go theorem: local causality, restated for records, is no longer at odds with the quantum statistics. This is possible because modularity, the inclusion-exclusion law of classical probability, fails across incompatible contexts, so that the probability theory generalizes Kolmogorov's. We exhibit explicit models reproducing several quantum strategies, including the optimal CHSH violation. More broadly, locally causal models of this kind attain every Bell-CHSH value up to the algebraic maximum. A realist explanation of the quantum predictions need not be conspiratorial; every causal influence posited by these models is reflected in the operational predictions.
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The core argument is told without mathematics in "A simple story" (Sec. I); the models proving the main result are in Secs. III F and IV B (Figs. 2 and 4). 43 pages, 6 figures
Bell's theorem is popularly stated as the inconsistency of quantum theory with local realism. Realism is here formalized by the ontological models framework, where elements of reality are points of a measurable space and probabilities obey the Kolmogorov axioms. In the Bell scenario, locally causal ontological models posit a common cause supporting a global valuation, a joint assignment of outcomes to all measurements at once, across incompatible contexts. Within this notion of realism, Bell's theorem makes any realist explanation of the quantum predictions conspiratorial: any mechanism, whether superluminal, superdeterministic, or retrocausal, must be finely tuned so as never to manifest operationally. We redefine realism through a new ontological framework that generalizes the standard one. The elements of reality, which we call records, are no longer points but relational parts of a point-free generalization of a topological space (sublocales of a locale). A record shared by two incompatible contexts establishes the sameness of a measurement across them, without such pairwise identities composing into a global valuation, and the common cause is then a web of such records. Within this framework, Bell's no-go theorem becomes a go theorem: local causality, restated for records, is no longer at odds with the quantum statistics. This is possible because modularity, the inclusion-exclusion law of classical probability, fails across incompatible contexts, so that the probability theory generalizes Kolmogorov's. We exhibit explicit models reproducing several quantum strategies, including the optimal CHSH violation. More broadly, locally causal models of this kind attain every Bell-CHSH value up to the algebraic maximum. A realist explanation of the quantum predictions need not be conspiratorial; every causal influence posited by these models is reflected in the operational predictions.
Bell's theorem states that no description of a Bell experiment can be simultaneously local, realistic in the sense of counterfactual definiteness, and free of conspiracy between settings and hidden state. The recent generation of experiments has confirmed the predicted violation of the CHSH inequality, so one of the assumptions must be abandoned. Which one, and how one reconstructs a coherent worldview after doing so, is a question on which many authors disagree. This paper is written by three such authors. All three reject both counterfactual definiteness and conspiratorial violation of statistical independence of setting choices and state. After a joint exposition of the classical half of Bell's theorem in the language of Pearl-style causal graphs, a joint summary of the loophole-free experiments, and a joint survey of the recent literature, each author states where they have presently arrived. Gill accepts irreducible and non-local quantum randomness and finds the choice between locality and realism a false dichotomy. In his later works, Bell derives counterfactual definiteness from classical local causality, and that is what has to go. The metaphysical concepts "realism", "locality", "causality" need to be reconsidered. Helland reconstructs the Hilbert-space formalism from a theory of accessible variables, and from this theory he concludes that every observer must be limited in a specific sense. Jongejan proposes a geometric hidden-variable construction in which the degree of violation of the CHSH inequality depends on the number of dimensions of space, Tsirelson's bound corresponding to three dimensions. The authors conclude with a discussion.
This open letter challenges Annals of Physics' Editors and Bell's supporters on this front: in the context of Bell's theorem -- after AoP (2016:67) -- ‘it's a proven scientific fact that a violation of local realism has been demonstrated theoretically and experimentally.' We show that such claims under the Bellian canon are curtailed by its foundation on a naive realism that is known to be false; ie, under Bohr's old insight (in our terms), a test may disturb the tested system. Further: (i) We define a general all-embracing local realism -- CLR, commonsense local realism -- the union of local-causality (no causal influence propagates superluminally) and physical-realism (some physical properties change interactively). (ii) Under CLR, with EPR-based variables (and without QM), a thought-experiment delivers a local-realistic account of EPRB and GHZ in 3-space. (iii) Under EPR, mixing common-sense with undergrad math/physics in the classical way so favored by Einstein, we interpret QM locally and realistically. (iv) We find the flaw in Bell's theorem: Bell's 1964:(14a) ≠ Bell's 1964:(14b) under EPRB. (v) EPR (1935) famously argue that additional variables will bring locality and causality to QM's completion; we show that they are right. (vi) Even more famously, Bell (1964) cried ‘impossible' against such variables; we give the shortest possible refutation of his claim. (vii) Using Bell's (1988:88) moot gloss on a fragment of von Neumann's work, we conclude: ‘There's nothing to Bell's theorem -- nor Bellian variants like CHSH (1969), Mermin (1990), Peres (1995); nor Bellian endorsements like those by Bricmont, du Sautoy, Goldstein et al., Maudlin, Norsen, Shimony -- it's not just flawed, it's silly; its assumptions nonsense; it's not merely false but foolish' and misleading. (viii) Our results accord with common-sense, QM, Einstein's principles, EPR's belief and Bell's hopes and expectations.
Rebooting Einstein's ideas about local-causality, an engineer brings local-causality to quantum theory via operators and variables in 3-space. Taking realism to be the view that external reality exists and has definite properties, his core principle is common-sense local realism (CLR): the union of local-causality (no causal influence propagates superluminally) and physical-realism (some physical properties change interactively). Endorsing Einstein-separability — system X is independent of what is done with system Y that is spatially separated from X — Bell's famous mission is advanced. That is, by means of parameters λ, a more complete specification of EPRB's physics is successful. A consequent locally-causal refutation of Bell's theorem allows EPRB correlations to be explained in a classical way, in line with Einstein's ideas, without reference to Hilbert space, quantum states, etc. Conclusion: Bell's theorem is based on a mathematical error; an error in reduction is inconsistent with Bell's opening assumptions.
Eschewing naive realism, we define true (classical/quantum) realism:= some existents (ie, some Bell-beables) may change interactively. We then show that Bell's mathematical ideas re local causality—from his 1964:(1)-(2) to his 1990a:(6.9.3)—are valid under true realism. But we refute Bell's analyses (and his ‘local realism’), as we resolve his consequent ‘action-at-a-distance’ dilemma in favor of true locality:= no influence propagates superluminally. In short: defining beables by properties and values—and allowing that locally-causal interactions may yield new beables—we predict the probabilities of such interaction outcomes via equivalence-classes that are weaker (hence more general) than the corresponding classes in EPR/Bell. In this way delivering the same results as quantum theory and experiment—using EPRB, CHSH, GHZ and 3-space—we also advance QM's reconstruction in spacetime with a new vector-product for geometric algebra. True local realism thus supports local causality, resolves Bell's dilemma, negates nonlocality, demystifies QM, rejects naive realism, eliminates the quantum/classical divide (since observables are clearly beables; being or not being, prior to an interaction, but certainly existing thereafter), etc: all at the level of undergraduate math and logic, and all contra the analyses and impossibility-claims of Bell and many others. We also show that Bayes' Law and Malus' Law hold, undiminished, under true local realism and the quantum.
An open letter to Bellians and the Annals of Physics' Editors re -- it's a proven scientific fact: a violation of local realism has been demonstrated theoretically and experimentally -- after AoP (2016:67). EPR (1935) famously argue that additional variables will bring locality and causality to QM's completion; we show that they are right. Even more famously, Bell (1964) cried ‘impossible' against such variables; we give the shortest possible refutation of his claims. With EPR-based variables (and without QM), an old thought-experiment delivers a commonsensical locally-causal account of EPRB and GHZ in 3-space. We then name the flaw in Bell's theorem – Bell's error -- Bell's 1964:(14a) ≠ Bell's 1964:(14b) under EPRB. Thus, given Bell's (1988:88) gloss on a snippet of von Neumann's work, ‘There's nothing to Bell's theorem -- nor variants like CHSH (1969), Mermin (1990), Peres (1995) -- it's not just flawed, it's silly; not merely false but foolish.' In short, we show that the whole Bellian canon -- with its no-name brand of local realism -- is all of those, and misleading too. Under EPR, mixing common-sense with undergrad math/physics in the classical way so favored by Einstein, we interpret QM locally and realistically. We thus define a new brand of local realism -- CLR, commonsense local realism -- the union of local-causality (no causal influence propagates superluminally) and physical-realism (some physical properties change interactively). Long may EPR rule OK we say.
Local realism must predict empirical Bell violations in a reasonable way to become a compelling causal explanation of reality. According to the paper at the link given below, it can now do that. On the other hand, theory, despite its wonderful statistical predictions, must transcend its infamous paradoxes to become a compelling causal explanation of anything. Unfortunately, paradoxes reduce to contradictions, and thus to nonsense. Take quantum superposition. Is this the simultaneous existence of mutually exclusive states or not? If it is, then we have a contradiction, and all further claims from theory fail to have meaningful interpretations. If superposition is something other than that contradiction, then what -- exactly -- is superposition? And let's take physical while we are at it. Defending theory as a causal explanation of reality requires that reality is not exclusively reality! Whoops. What -- exactly -- is so difficult about simply admitting when we have no sensible causal explanation for certain phenomena like Bell violations in EPR(B) experiments? In psychology, we know the answer to such questions. Our beliefs are evidence resistant. We thus predict that the rational threat from local realism to widespread beliefs -- its implication that reality might be mostly explained without appeal to antilocal mysticism -- will continue to be buried under reams of empirical observations stitched together by nonsense insinuations that that paradoxes are assets rather than contradictions. In any case, the paper below arguably formulates a theory of local realism that constitutes a causally valid description of reality. No nonsense required. Or, it could just be wrong. But it is waiting to be tested. Indeed, even existing data could bear on the empirical question if the theory is sound enough. See ** http://vixra.org/abs/1704.0078 ** Local Realism Explains Bell Violations (author Andrew P. Yake) - for a demonstration that all empirical evidence taken to support theory over local realism plausibly does the reverse. The article comprises 8 pages, 4 figures, 6 equations, 32 references, a graph of testable predictions, and two paragraphs that purport to expose how the Bell inequality misrepresents the local realistic predictions for the EPR experiment. Thoughtful feedback appreciated (apyake@gmail.com).