Digital Quantum Reality

In our quest for a local and realistic description of quantum mechanics we have developed a full concrete model incorporating many aspects of quantum behavior (quantization, uncertainty principle, wave-particle duality, Born rule, momentum entanglement, etc.), which we have been presenting in previous posts. However, a further class of genuine quantum processes requires a description of an additional particle property, which is intrinsic  spin . I have recently added spin in my model, as reported in my most recent ArXiv publication . With this post, we are going to discuss how spin can emerge from a more fundamental local-realistic mechanism. In addition to source momentum, particles have an intrinsic property that is a rational number comprised between -1 and +1, which we shall call " source spin " and denote as s 0 . In addition to momentum polarization , they also have another vector quantity, that is, three rational numbers {μ 0d } such that We shall call th...

In a previous post , we have discovered that quantum mechanics can described equivalently to standard approaches, and in particular Bell's inequalities  can be violated in a Bell test with momentum-entangled pairs of particles, despite making use of local realist assumptions. However, it is a fact that Bell's theorem and its descendants are regularly used to dismiss any possibility that a local-realist quantum mechanical model could even exist. John Stewart Bell (1928-1990) How happens that our local-realist model captures BI violations and correctly reproduces QM statistics? How to solve this apparent paradox? Despite its mathematical simplicity, interpretation of Bell's theorem has given rise to a vast literature, in particular concerning its assumptions and the conclusions that can be drawn. The usual assumptions used in deriving Bell inequalities are realism (properties of physical systems are elements of reality, outcomes of tests are determined by some hidde...

Within our search for a local-realist description of quantum mechanics, two recent posts have discussed the local-realist rules of motion for particle pairs that are entangled in momentum and how position probability distributions are built upon. We want now to describe a scenario for which these rules allow to retrieve typical quantum correlations between the two particles, which ultimately lead to violations of Bell's inequalities as predicted for QM by Bell's theorem . The scenario consists of a two-slit interferometer, as depicted in the figure. This setting is equivalent to the double-source preparation discussed in the aforementioned posts. The two 'sources' are equally probable and the phase difference at each station is ε (I) = α, ε (II) = β. The detectors are placed at positions x ±  = ±t/(4D), where δ = 2D is the distance between the two slits, a parameter of the stations. In the case of a single station active, with particles emitted ...

When I submitted my manuscript to the journal Foundations of Physics , one of the referees was pointing out that The positive model developed in this manuscript represents a lot of careful work, and exhibits a solid grasp on the foundational literature. To my mind, the fatal flaw is the failure to discuss multiparticle systems. It's a fatal flaw because the paper purports to develop a local realistic model of quantum phenomena. Well-known impediments to the empirical adequacy of such models (e.g. the Bell inequalities ) arise in the presence of entanglement between particles. A revised version of the paper that shows how the model recovers standard QM's prediction of the violation of Bell-type inequalities would make a much stronger case that the model is worth taking seriously. (Such a recovery needn't entail extending the model to incorporate spin phenomena: the Bell-correlated observables needn't be spin observables.) [bold mine] I therefore started incorporatin...

In this blog we are presenting and supporting a local and realist model for quantum mechanics , based on simple rules of (stochastic) motion on a discrete spatiotemporal lattice. The model is realist in the sense that at each instant particles have definite properties such as position, momentum, energy, etc. and these are independent of any possible measurement. Locality means that particles interact only with other beables that are resident in the lattice nodes actually visited. In particular, quantum behavior is reproduced for an ensemble of similarly-prepared particles and thanks to a footprint mechanism where particles leave some information in the node they visit which influece the behavior of subsequent particles. One of the most common objections to the fact that one even tries to build a local and realist model, is that these models are simply impossible, as they are supposedly ruled out by Bell 's theorem . In this post and in future ones we shall demonstrate that the op...

(Cover image from: A.G. Manning, R.I. Khakimov, R.G. Dall, and A.G. Truscott, "Wheeler’s delayed-choice gedanken experiment with a single atom", Nature Physics, vol. 11, July 2015, DOI: 10.1038/NPHYS3343) In previous posts, we have discussed several quantum mechanics scenarios (for example here , here , here , etc.) and seen how they are perfectly reproduced by our local-realistic model , both theoretically and numerically. In this post we shall describe a further test for our model, that is reproducing the non-classical behavior of interferometers. We shall consider in particular  atom interferometers , and leave those operating with photons to when we shall treat quantum electrodynamics. A rather general interferometer scheme, shown in the figure below, consists of: (i) a source S where a beam in a particular state is prepared, (b) a first splitting of the beam into two paths, BS1, with different momentum states and phases (iii) a recombination M of the two paths (...

In a previous post we have described the rules that apply at each " External Reset ", that is, when a particle encounters an external force-carrier, an external "boson". In particular, the span is reversed according to the 1D rule (1) which is generalized to the 3D rule described in this post  (2), where the resulting spans are intended to be rounder at the nearest integer. However, these rules alone are not sufficient to represent the emergence of quantum behavior such as self-interference and superposition. Thus, it is now time for some more details. Let us come back to the double slit experiment. Consider such an apparatus as illustrated in the figure below, where O is the source of particles, S1 and S2 are the two slits, and P is the recording screen. In standard QM the wave function at the screen is obtained as the superposition of two wave functions emitted at slits S1 and S2 and propagated to the screen. This is possible because of th...