Realist Interpretation Of Quantum Mechanics Research Articles

Chemical reduction and quantum interpretation: A case for thomistic emergence

The debate between ontological reductionists and emergentists in chemistry has revolved around quantum mechanics. What Franklin and Seifert (BJPS 2020) add to the long-running dispute is an attention to the measurement problem. They contend that all three realist interpretations of the quantum formalism capable of resolving the measurement problem also obviate any need for chemical emergence. I push their argument further, arguing that the realist interpretations of quantum mechanics actually subvert the basis for reduction as well, by undercutting the idea that fundamental physical particles are actual parts of molecules. With both reduction and traditional synchronic emergence pictures ruled out, the only option for realists about quantum chemistry is strong Thomistic emergence.

Quantum Clones inside Black Holes

A systematic procedure is proposed for better understanding the evolution laws of black holes in terms of pure quantum states. We start with the two opposed regions I and II in the Penrose diagram, and study the evolution of matter in these regions, using the algebra derived earlier from the Shapiro effect in quantum particles. Since this spacetime has two distinct asymptotic regions, one must assume that there is a mechanism that reduces the number of states. In earlier work we proposed that region II describes the angular antipodes of region I, the ‘antipodal identification’, but this eventually leads to contradictions. Our much simpler proposal is now that all states defined in region II are exact quantum clones of those in region I. This indicates more precisely how to restore unitarity by making all quantum states observable, and in addition suggests that generalisations towards other black hole structures will be possible. An apparent complication is that the wave function must evolve with a purely antisymmetric, imaginary-valued Hamiltonian, but this complication can be well-understood in a realistic interpretation of quantum mechanics.

Quantum Non-Locality and the CMB: What Experiments Say

“Non-locality is most naturally incorporated into a theory in which there is a special frame of reference. One possible candidate for this special frame of reference is the one in which the Cosmic Microwave Background (CMB) is isotropic. However, other than the fact that a realistic interpretation of quantum mechanics requires a preferred frame and the CMB provides us with one, there is no readily apparent reason why the two should be linked” (L. Hardy). Starting from this remark, we first argue that, given the present view of the vacuum, the basic tenets of Quantum Field Theory cannot guarantee that Einstein Special Relativity, with no preferred frame, is the physically realized version of relativity. Then, to try to understand the nature of the hypothetical preferred Σ−frame, we consider the so-called ether drift experiments, those precise optical measurements that try to detect, in the laboratory, a small angular dependence of the two-way velocity of light and then to correlate this angular dependence with the direct CMB observations with satellites in space. By considering all experiments performed so far, from Michelson–Morley to the present experiments with optical resonators, and analyzing the small observed residuals in a modern theoretical framework, the long-sought Σ−frame tight to the CMB naturally emerges. Finally, if quantum non-locality reflects some effect propagating at vastly superluminal speed vQI→∞, its ultimate origin could be hidden somewhere in the infinite speed cs→∞ of vacuum density fluctuations.

Quantum modal indeterminacy

The paper investigates the existence and the nature of quantum indeterminacy in a particular realist interpretation of quantum mechanics, that is, the Modal Hamiltonian Interpretation (MHI)—together with an ontology of properties for quantum systems. In doing so, it serves a twofold purpose. First, it advances the debate on quantum ontology by showing precisely how and why indeterminacy arises in a quantum world—as described by the MHI. Second, it offers a naturalistic example of genuine metaphysical indeterminacy, an example coming from our best physics.

Underdetermination: A Realist Interpretation of Quantum Mechanics and Bohmian Mechanics

Underdetermination: A Realist Interpretation of Quantum Mechanics and Bohmian Mechanics

Possibility and Time in Quantum Mechanics.

In the discourse of quantum mechanics it is usual to say that non-commuting observables cannot have definite values at the same time, or that they cannot be simultaneously measured. But, what does the term ‘cannot’ mean in this context? Does it stand for impossible? Should Heisenberg’s principle be read in terms of uncertainty or of indeterminacy? On the other hand, whereas the debates about the nature of time in classical and relativistic mechanics have been many and varied, the question about the nature of time in quantum mechanics has not received the same attention, especially when compared to the large amount of literature on interpretive issues. The purpose of this paper is to show that, under a realist interpretation of quantum mechanics, these two matters, possibility and time, are strongly related. The final aim is to argue that, when possibility and actuality are conceived as irreducible modes of being, they are correlated to two different notions of time that can be distinguished in the quantum realm: parameter-time and event-time.

Realistic Simulations of EPR Experiments: Nonlinear Concept for New Principle of Non-Locality and for Realistic Interpretation of Quantum Mechanics

Realistic Simulations of EPR Experiments: Nonlinear Concept for New Principle of Non-Locality and for Realistic Interpretation of Quantum Mechanics

Conceiving Particles as Undulating Granular Systems Allows Fundamentally Realist Interpretation of Quantum Mechanics.

The strange behavior of subatomic particles is described by quantum theory, whose standard interpretation rejected some fundamental principles of classical physics such as causality, objectivity, locality, realism and determinism. Recently, a granular relativistic electrodynamical model of the electron could capture the measured values of its observables and predict its mass from the stability of its substructure. The model involves numerous subparticles that constitute some tight nucleus and loosely bound envelope allegedly forming real waves. The present study examines whether such a substructure and associated dynamics allow fundamentally realist interpretations of emblematic quantum phenomena, properties and principles, such as wave-particle duality, loss of objectivity, quantization, simultaneous multipath exploration, collapse of wavepacket, measurement problem, and entanglement. Drawing inspiration from non-linear dynamical systems, subparticles would involve realist hidden variables while high-level observables would not generally be determined, as particles would generally be in unstable states before measurements. Quantum mechanics would constitute a high-level probabilistic description emerging from an underlying causal, objective, local, albeit contextual and unpredictable reality. Altogether, by conceiving particles as granular systems composed of numerous extremely sensitive fluctuating subcorpuscles, this study proposes the possible existence of a local fundamentally realist interpretation of quantum mechanics.

The View from a Wigner Bubble

In a recent no-go theorem [Bong et al, Nature Physics (2020)], we proved that the predictions of unitary quantum mechanics for an extended Wigner's friend scenario are incompatible with any theory satisfying three metaphysical assumptions, the conjunction of which we call "Local Friendliness": Absoluteness of Observed Events, Locality and No-Superdeterminism. In this paper (based on an invited talk for the QBism jubilee at the 2019 Vaxjo conference) I discuss the implications of this theorem for QBism, as seen from the perspective of experimental metaphysics. I argue that the key distinction between QBism and realist interpretations of quantum mechanics is best understood in terms of their adherence to different theories of truth: the pragmatist versus the correspondence theories. I argue that a productive pathway to resolve the measurement problem within a pragmatist view involves taking seriously the perspective of quantum betting agents, even those in what I call a "Wigner bubble". The notion of reality afforded by QBism, I propose, will correspond to the invariant elements of any theory that has pragmatic value to all rational agents -- that is, the elements that are invariant upon changes of agent perspectives. The classical notion of `event' is not among those invariants, even when those events are observed by some agent. Neither are quantum states. Nevertheless, I argue that far from solipsism, a personalist view of quantum states is an expression of its precise opposite: Copernicanism.

The Quantum Handshake: An Electric Charge/Transactional Interpretation of the Single Electron Double-Slit Experiment

A new and falsifiable realist interpretation of quantum mechanics is examined in relation to the sum over histories concept, pilot wave theory and the many-worlds interpretation. This electric charge/transactional model explains how the single electron double-slit experiment produces extremely localized endpoints from diffracted wavicles, why these endpoints are scattered around the entire surface of the absorber screen, and why these points of contact result in the characteristic fringe pattern as they accumulate. Advanced waves and substantive electric charge effects in the double-slit experiment are postulated, then this hypothesis is supported by a quantitative analysis of electron emission in comparison to lightning. The wider implications if advanced waves and electric charge distribution prove to be significant factors in the double-slit experiment are discussed, including possible parallels with meteorological and neurological phenomena.

A Puzzle for the Field Ontologists

It has been widely thought that the wave function describes a real, physical field in a realist interpretation of quantum mechanics. In this paper, I present a new analysis of the field ontology for the wave function. First, I argue that the non-existence of self-interactions for a quantum system such as an electron poses a puzzle for the field ontologists. If the wave function represents a physical field, then it seems odd that there are (electromagnetic and gravitational) interactions between the fields of two electrons but no interactions between two parts of the field of an electron. Next, I argue that the three solutions a field ontologist may provide are not fully satisfactory. Finally, I propose a solution of this puzzle that leads to a particle ontological interpretation of the wave function.

Quantum Reality, Perspectivalism and Covariance

Paul Busch has emphasized on various occasions the importance for physics of going beyond a merely instrumentalist view of quantum mechanics. Even if we cannot be sure that any particular realist interpretation describes the world as it actually is, the investigation of possible realist interpretations helps us to develop new physical ideas and better intuitions about the nature of physical objects at the micro level. In this spirit, Paul Busch himself pioneered the concept of “unsharp quantum reality”, according to which there is an objective non-classical indeterminacy—a lack of sharpness—in the properties of individual quantum systems. We concur with Busch’s motivation for investigating realist interpretations of quantum mechanics and with his willingness to move away from classical intuitions. In this article we try to take some further steps on this road. In particular, we pay attention to a number of prima facie implausible and counter-intuitive aspects of realist interpretations of unitary quantum mechanics. We shall argue that from a realist viewpoint, quantum contextuality naturally leads to “perspectivalism” with respect to properties of spatially extended quantum systems, and that this perspectivalism is important for making relativistic covariance possible.

Decoherence and Intertheory Relations in Quantum Realism

The complex relation between quantum mechanics and classical mechanics is crucial in the philosophy of modern physics, and it cuts across current quantum physics. This paper is divided in two parts. In the first part I will offer a critical analysis of the role that decoherence plays in the account of the quantum-classical limit. In the second part I will mention three ways in which philosophers are engaging with the realist interpretation of quantum mechanics in light of the assessment that the problem of the quantum-classical limit is still open to debate. My main claim is that the problem of the quantum-classical limit is overrated and it receives too much attention for the realist who looks at quantum mechanics. The question that the realist wants to focus on is the crucial interpretation question: what is a quantum system?

Causation does not explain contextuality

Realist interpretations of quantum mechanics presuppose the existence of elements of reality that are independent of the actions used to reveal them. Such a view is challenged by several no-go theorems that show quantum correlations cannot be explained by non-contextual ontological models, where physical properties are assumed to exist prior to and independently of the act of measurement. However, all such contextuality proofs assume a traditional notion of causal structure, where causal influence flows from past to future according to ordinary dynamical laws. This leaves open the question of whether the apparent contextuality of quantum mechanics is simply the signature of some exotic causal structure, where the future might affect the past or distant systems might get correlated due to non-local constraints. Here we show that quantum predictions require a deeper form of contextuality: even allowing for arbitrary causal structure, no model can explain quantum correlations from non-contextual ontological properties of the world, be they initial states, dynamical laws, or global constraints.

Erratum to: Realistic interpretation of quantum mechanics and encounter-delayed-choice experiment

Erratum to: Realistic interpretation of quantum mechanics and encounter-delayed-choice experiment

Realistic interpretation of quantum mechanics and encounter-delayed-choice experiment

In this paper, a realistic interpretation (REIN) of the wave function in quantum mechanics is briefly presented. We demonstrate that in the REIN, the wave function of a microscopic object is its real existence rather than a mere mathematical description. Specifically, the quantum object can exist in disjointed regions of space just as the wave function is distributed, travels at a finite speed, and collapses instantly upon a measurement. Furthermore, we analyze the single-photon interference in a Mach-Zehnder interferometer (MZI) using the REIN. Based on this, we propose and experimentally implement a generalized delayed-choice experiment, called the encounter-delayed-choice experiment, where the second beam splitter is decided whether or not to insert at the encounter of two sub-waves along the arms of the MZI. In such an experiment, the parts of the sub-waves, which do not travel through the beam splitter, show a particle nature, whereas the remaining parts interfere and thus show a wave nature. The predicted phenomenon is clearly demonstrated in the experiment, thus supporting the REIN idea.

Beyond Bell\u2019s theorem: realism and locality without Bell-type correlations

The long-lasting view of entanglement as the characteristic trait of quantum mechanics has been recently challenged by experimental demonstrations of non-quantum entanglement. This motivates a review of the meaning of Bell violations, which have been widely taken to prove the impossibility of a realistic interpretation of quantum mechanics and as a manifestation of its non-local character. This work provides new theoretical evidence for the need of reviewing the meaning of Bell violations, especially when they occur outside the quantum framework. We present a local-realistic model that reproduces quantum predictions concerning Bell tests. We claim that local-realism is fully compatible with correlations that are not of the Bell type and therefore lie outside the scope of Bell’s theorem. Most experimental Bell tests involve either spin vectors spanning the Bloch sphere or Stokes vectors spanning the Poincaré sphere. A suitable statistical tool that allows assessing correlations between vectors is given by inner-product-type correlations. Using them, it is possible to reproduce quantum predictions for all Bell states, thereby explaining experimental results of Bell tests within a local-realistic framework.

Towards a Realistic Interpretation of Quantum Mechanics Providing a Model of the Physical World

It is argued that a realistic interpretation of quantum mechanics is possible and useful. Current interpretations, from Copenhagen to many worlds are critically revisited. The difficulties for intuitive models of quantum physics are pointed out and possible solutions proposed. In particular the existence of discrete states, the quantum jumps, the alleged lack of objective properties, measurement theory, the probabilistic character of quantum physics, the wave-particle du- ality and the Bell inequalities are analyzed. The sketch of a realistic picture of the quantum world is presented. It rests upon the assump- tion that quantum mechanics is a stochastic theory whose randomness derives from the existence of vacuum fields. They correspond to the vacuum fluctuations of quantum field theory, but taken as real rather than virtual.

The aim and scope of scientific metaphysics

Over the recent years, the pursuit of scientific metaphysics has become a central enterprise in the philosophy arena. Issues about the nature of metaphysical research, the scope of metaphysical knowledge, and the role of metaphysics within the human Enlightenment project of the sciences have rapidly experienced a vivid renaissance. The volume under review undoubtedly presents an outstanding, cutting-edge contribution to this debate, and it may well be considered as the most comprehensive and philosophically penetrating book of its kind. The volume is comprised of ten independent papers. Contributors are Anjan Chakravartty, Daniel Dennett, Michael Friedman, Paul Humphreys, Jenann Ismael, Harold Kincaid, James Ladyman, Andrew Melnyk, Don Ross, and Mark Wilson. Among the main issues addressed are the state of art of scientific metaphysics (Chapter 1), problems regarding the prospects of naturalized metaphysics (Chapter 2), the critique of speculative ontology (Chapter 3), analysis of the naturalization project (Chapter 4), the bestiary of the manifest image (Chapter 5), the structural realist interpretation of quantum mechanics (Chapter 6), the influence of the scientific philosophy heritage on the contemporary debate (Chapter 7), the relativised Kantianstyle conception of scientific rationality (Chapter 8), remarks on naturalism (Chapter 9), and the place of free will within scientific ontology (Chapter 10). Throughout this review, I examine three core issues: first, problems resulting from the viability of scientific metaphysics; second, the critique of a priori analytic metaphysics; and third, a new positive attempt to pursue a scientific metaphysics. As

Realist model approach to quantum mechanics

The paper proves that quantum mechanics is compatible with the constructive realism of modern philosophy of science. The proof is based on the observation that properties of quantum systems that are uniquely determined by their preparations can be assumed objective without the difficulties that are encountered by the same assumption about values of observables. The resulting realist interpretation of quantum mechanics is made rigorous by studying the space of quantum states—the convex set of state operators. Prepared states are classified according to their statistical structure into indecomposable and decomposable instead of pure and mixed. Simple objective properties are defined and showed to form a Boolean lattice.