Quantum Theory as a Hidden Variables Theory

In our terms, this is Bell's 1964 theorem, 'No local hidden-variable theory can reproduce exactly the quantum mechanical predictions.' Against this, and bound by what Bell takes to be Einstein's definition of locality, we refute Bell's theorem and reveal his error. We show that Einstein was right: the physical world is local; and we advance Einstein's quest to make quantum mechanics intelligible in a classical way. With respect to understanding, and taking mathematics to be the best logic, the author is as close as an email.

Studies in History and Philosophy of Modern Physics, 1996

It is argued that for a proper understanding of the question of nonlocality in quantum mechanics and hidden variables theories purporting to reproduce the quantum mechanical measurement results, it is essential to consider stochastic hidden variables theories. conclusion that in derivations of the Bell inequality an implicit assumption of locality is made, is shown to be a consequence of his restriction to deterministic hidden variables theories. It is also demonstrated how it is possible to draw a clear distinction between contextualism and non-objectivism, nonobjectivism amounting to the impossibility of reducing an individual quantum mechanical measurement result, either in a deterministic or in a stochastic way, to the hidden variables state the individual object is in independently of the measurement. The analogy with thermodynamics is exploited to clarify the issue.

Combining twenty-six original essays written by an impressive line-up of distinguished physicists and philosophers of physics, this anthology reflects some of the latest thoughts by leading experts on the influence of Bell's theorem on quantum physics. Essays progress from John Bell's character and background, through studies of his main work, and on to more speculative ideas, addressing the controversies surrounding the theorem, and investigating the theorem's meaning and its deep implications for the nature of physical reality. Combined, they present a powerful comment on the undeniable significance of Bell's theorem for the development of ideas in quantum physics over the past 50 years. Questions surrounding the assumptions and significance of Bell's work still inspire discussion in the field of quantum physics. Adding to this with a theoretical and philosophical perspective, this balanced anthology is an indispensable volume for students and researchers interested in the philosophy of physics and the foundations of quantum mechanics.

Quantum [Un]Speakables II

Non-locality, or quantum-non-locality, are buzzwords in the community of quantum foundation and information scientists, which purportedly describe the implications of Bell's theorem. When such phrases are treated seriously, that is it is claimed that Bell's theorem reveals non-locality as an inherent trait of the quantum description of the micro-world, this leads to logical contradictions, which will be discussed here. In fact, Bell's theorem, understood as violation of Bell inequalities by quantum predictions, is consistent with Bohr's notion of complementarity. Thus, if it points to anything, then it is rather the significance of the principle of Bohr, but even this is not a clear implication. Non-locality is a necessary consequence of Bell's theorem only if we reject complementarity by adopting some form of realism, be it additional hidden variables, additional hidden causes, etc., or counterfactual definiteness. The essay contains two largely independent parts. The first one is addressed to any reader interested in the topic. The second, discussing the notion of local causality, is addressed to people working in the field.

2020

Here it is shown that the simplest description of Bell's experiment according to the canon of von Neumann's theory of measurement explicitly assumes the (Quantum Mechanics-language equivalent of the classical) condition of Locality. This result is complementary to a recently published one demonstrating that non-Locality is necessary to describe said experiment within the framework of classical hidden variables theories, but that it is unnecessary to describe it within the framework of Quantum Mechanics. Summing up these and other related results, it is concluded that, within the framework of Quantum Mechanics, there is absolutely no reason to believe in the existence of non-Local effects. In addition to its foundational significance, this conclusion has practical impact in the fields of quantum-certified and device-independent randomness generation and on the security of Quantum Key Distribution schemes using entangled states.

The purposes of the present article are: a) To show that non-locality leads to the transfer of certain amounts of energy and angular momentum at very long distances, in an absolutely strange and unnatural manner, in any model reproducing the quantum mechanical results. b) To prove that non-locality is the result only of the zero spin state assumption for distant particles, which explains its presence in any quantum mechanical model. c) To reintroduce locality, simply by denying the existence of the zero spin state in nature (the so-called highly correlated, or EPR singlet state) for particles non-interacting with any known field. d) To propose a realizable experiment to clarify if two remote (and thus non-interacting with a known field) particles, supposed to be correlated as in Bell-type experiments, are actually in zero spin state.

Foundations of Physics, 2015

It is shown that Quantum Mechanics is ambiguous when predicting relative frequencies for an entangled system if the measurements of both subsystems are performed in spatially separated events. This ambiguity gives way to unphysical consequences: the projection rule could be applied in one or the other temporal(?) order of measurements (being non local in any case), but symmetry of the roles of both subsystems would be broken. An alternative theory is presented in which this ambiguity does not exist. Observable relative frequencies differ from those of orthodox Quantum Mechanics, and a gendaken experiment is proposed to falsify one or the other theory. In the alternative theory, each subsystem has an individual state in its own Hilbert space, and the total system state is direct product (rank one) of both, so there is no entanglement. Correlation between subsystems appears through a hidden label that prescribes the output of arbitrary hypothetical measurements. Measurement is treated as a usual reversible interaction, and this postulate allows to determine relative frequencies when the value of a magnitude is known without in any way perturbing the system, by measurement of the correlated companion. It is predicted the existence of an accompanying system, the de Broglie wave, introduced in order to preserve the action reaction principle in indirect measurements, when there is no interaction of detector and particle. Some action on the detector, different from the one cause by a particle, should be observable.

2015

Alhun Aydın, 2011

Although standard quantum mechanics is compatible with experiments, it could not clarify some important unsolved problems like quantum reality and measurement process. Hidden variable theories provide solutions to these conceptual problems of standard quantum mechanics. We examine Bell's theorem, one of the most essential theorems about foundations of quantum mechanics, and Bell-test experiments which empirically rules out local hidden variable theories. Then we discuss pilot wave theory which is a non-local hidden variable theory and one of the most significant possible successors of standard quantum mechanics. Moreover, by touching upon also philosophical issues, we give the shape of the possible interpretation of quantum mechanics.