34 results on '"De Broglie–Bohm theory"'
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2. Quantum pointillism with relational identity
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Manero, Jorge
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- 2021
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3. The wave-function as a multi-field
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Hubert, Mario and Romano, Davide
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- 2018
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4. Emergent evolutionism, determinism and unpredictability
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Olivier Sartenaer and UCL - SSH/ISP - Institut supérieur de philosophie
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History ,De Broglie–Bohm theory ,Determinism ,media_common.quotation_subject ,Interpretation (philosophy) ,Physics ,Doctrine ,Emergence ,Predictability ,Chaos theory ,Hard determinism ,Epistemology ,Philosophy ,Emergent evolutionism ,History and Philosophy of Science ,Nonlinear Dynamics ,Free will ,Quantum Theory ,Chaos ,Sociology ,Evolutionism ,Bohmian mechanics ,media_common - Abstract
The fact that there exist in nature thoroughly deterministic systems whose future behavior cannot be predicted, no matter how advanced or fined-tune our cognitive and technical abilities turn out to be, has been well established over the last decades or so, essentially in the light of two different theoretical frameworks, namely chaos theory and (some deterministic interpretation of) quantum mechanics. The prime objective of this paper is to show that there actually exists an alternative strategy to ground the divorce between determinism and predictability, a way that is older than – and conceptually independent from – chaos theory and quantum mechanics, and which has not received much attention in the recent philosophical literature about determinism. This forgotten strategy – embedded in the doctrine called “emergent evolutionism” – is nonetheless far from being a mere historical curiosity that should only draw the attention of philosophers out of their concern for comprehensiveness. It has been indeed recently revived in the works of respected scientists. more...
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- 2015
5. Spin-Dependent Bohm Trajectories for Pauli and Dirac Eigenstates of Hydrogen
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Colijn, C. and Vrscay, E. R.
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- 2003
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6. Quantum Logic and the Unity of Science
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Kent A. Peacock and John Woods
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De Broglie–Bohm theory ,Theoretical physics ,Computer science ,Logical truth ,Classical logic ,Interpretations of quantum mechanics ,Principle of bivalence ,Quantum logic ,Quantum computer ,Unity of science - Abstract
This paper is an exploratory prolegomenon to the construction of a quantum logic that could shed some light on the thesis of the unity of science. We attempt to take account of the following factors, among others: the difficulty of saying just what a logic is, the startlingly simplequeerness of quantum mechanics from the classical point of view, the consequences of the breakdown of bivalence and individuation in quantum mechanics, and the implications of recent work in quantum computation for quantum logic. We tentatively endorse modal interpretations of quantum mechanics, and suggest that quantum computation points to ways in which quantum logic could be extended beyond the traditional Birkhoff-von Neumann lattice theoretic approach. more...
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- 2009
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7. Bohmian Mechanics on Information Spaces
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Andrei Khrennikov
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Statistical ensemble ,Formalism (philosophy of mathematics) ,symbols.namesake ,De Broglie–Bohm theory ,Cognitive systems ,Classical mechanics ,Information space ,Differential equation ,symbols ,Material system ,Schrödinger equation ,Mathematics - Abstract
In this chapter we develop the formalism of classical information mechanics by analogue to the formalism of the ordinary Newton mechanics which describes the motion of material systems. We propose information analogues of Newton’s laws of classical mechanics. Mathematically these laws can be described by differential equations in I-spaces. Starting with an initial I-state x 0, we obtain the trajectory q(t) in I-space. more...
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- 2004
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8. Bohmian Mechanics for Financial Processes
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Andrei Khrennikov
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Finance ,Computer Science::Computer Science and Game Theory ,Pilot wave ,De Broglie–Bohm theory ,business.industry ,Industrial production ,Phase space ,Financial market ,business ,Psychology ,Natural resource ,Information exchange ,Market conditions - Abstract
In this Chapter we use methods of classical and quantum mechanics for mathematical modeling of price dynamics in the financial market. The Hamil-tonian formalism on the price/price-change phase space is used to describe the classical-like evolution of prices. This classical dynamics of prices is determined by ‘hard’ conditions (natural resources, industrial production, services, and so on). These conditions as well as ‘hard’ relations between traders in the financial market are mathematically described by the classical financial potential. In the real financial market ‘hard’ conditions are not the only source of price changes. The information exchange and market psychology play important (and sometimes determining) roles in price dynamics. We propose to describe this ‘soft’ financial factors by using the pilot wave (Bohmian) model of quantum mechanics. The theory of financial mental (or psychological) waves is used to take into account market psychology. The real trajectories of prices are determined (by the financial analogue of Newton’s second law) by two financial potentials: classical-like (‘hard’ market conditions) and quantum-like (‘soft’ market conditions)1. more...
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- 2004
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9. Bell, Bohm, and Von Neumann: Some Philosophical Inequalities Concerning No-Go Theorems and the Axiomatic Method
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Michael Stöltzner
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symbols.namesake ,De Broglie–Bohm theory ,Local hidden variable theory ,Bell's theorem ,Hidden variable theory ,Calculus ,symbols ,Axiomatic system ,Bell test experiments ,Physics::History of Physics ,Mathematics ,Von Neumann architecture ,Kochen–Specker theorem - Abstract
The present paper investigates the philosophical relationship between John von Neumann’s Nohidden-variable theorem and Bell’s inequalities. Bell erroneously takes the axiomatic method as implying a finality claim and thus ignores von Neumann’s strongly pragmatist stance towards mathematical physics. If one considers, however, Hilbert’s axiomatic method as a critical enterprise, Bell’s theorem improves von Neumann’s by defining a more appropriate notion of ‘ hidden variable’ that permits one to include Bohm’s interpretation which recovers the predictive content of quantum mechanics. Contrary to Bell’s belief, accepting this model does not require adopting the metaphysically realist Bohm picture. If one takes the latter as a physical research programme one sees that it only partly disputes a common domain of facts with the mathematically oriented research programme of von Neumann. more...
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- 2002
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10. Bohm & Vigier: Ideas as A Basis for A Fractal Universe
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C. Ciubotariu, Ciprian Ciubotariu, and Viorel Stancu
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Physics ,De Broglie–Bohm theory ,symbols.namesake ,Classical mechanics ,Fractal ,Uncertainty principle ,Spacetime ,Quantum cosmology ,symbols ,Fractal dimension ,Schrödinger equation ,Fractal cosmology - Abstract
Bohm and Vigier introduced the notion of random fluctuations occurring from interaction with a subquantum medium. Fenyes-Nelson’s stochastic mechanics generalises these ideas in terms of a Markov process and tries to reconcile the individual particle trajectory notion with the quantum (Schrodinger) theory. Bohm-Vigier deterministic trajectories are in fact the mean displacement paths of the underlying Nelson’s diffusion process. However, random paths of stochastic mechanics are quite akin to Feynman paths which are non-differentiable and thus have fractal properties in the Mandelbrot sense. How a random field makes particles to propagate? This is the question. Can we speak about a stochastic acceleration property of (vacuum) spacetime which has stochastic (and chaotic) features? Can this offer an explanation of the inertial properties of matter? What is the source of randomness? The present paper tries to find an answer to these questions in the framework of the universality of a fractal structure of spacetime and of stochastic acceleration. Some arguments in favour of a fractal structure of spacetime at small and large scales areas follows. (i) Fractal trajectories in space with Hausdorff dimension 2 (e.g. a Peano-Moore curve) exhibit both an uncertainty principle and a de Broglie relation. Quantum mechanical particles move statistically on such fractal (Feynman) paths. Thus, Schrodinger equation may be interpreted as a fractal signature of spacetime. (ii) The formal analytic continuation (t → it or D → iD) iD) which relates the Schrodinger and diffusion equations has a physical alternative: there exists a (classical or quantum) stochastic fluid which can be either a fluid of probability for a unique element or a real fluid composed of elements undergoing quasi-Brownian motion. A particle (corpuscule) may be one or a small cluster of stochastic elements. There is a sort of democracy (statistical self-similarity) between the stochastic elements constituting the particle. As regards the cause of the randomness, the parton model involves a fragmentation of the partons. (iii) Nature does not “fractalize” (and quantize); it is intrinsically fractal (and quantum). Wave function of the universe is a solution of the Wheeler-DeWitt equation of quantum cosmology and corresponds to a Schrodinger equation. This can be related to the fact that observations of galaxy-galaxy and clustercluster correlations as well as other large-scale structure can be fit with a fractal with D ≈ 1.2 which may have grown from two-dimensional sheetlike objects such as domain walls or string wakes. The fractal dimension D can serve as a constraint on the properties of the stochastic motion responsible for limiting the fractal structure. (iV) The nonlinear (soliton) equation corresponds to a (linear) Schrodinger equation coupled to a medium with a specific nonlocal response. Physically, this model is similar to a simple case of linear propagation of thin beams in a wave guide. Thus, a free photon in (fractal) space represents in fact a “bouncing ball” in a wave guide. In other words, spacetime is structured as a (fractal) web of optical fibers (channels) which represents the skeleton of spacetime. (V) The proper wave functions describing a hydrogen-like atom (ψ1, ψ2, ψ3, ...) describing a hydrogen-like atom are similar to the electromagnetic modes (TEM 0 , TEM 1 , TEM 2 , ...) in optical resonating cavities. more...
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- 2002
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11. Non-locality and Modality
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Tomasz Placek and Jeremy Butterfield
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De Broglie–Bohm theory ,Quantum Physics ,Quantum entanglement ,Interpretations of quantum mechanics ,Physics::History of Physics ,symbols.namesake ,Theoretical physics ,Local hidden variable theory ,symbols ,EPR paradox ,Copenhagen interpretation ,Relational quantum mechanics ,Mathematics ,No-communication theorem - Abstract
Preface. Part One: Re-Examining the Legacy of Bohr and von Neumann. Reconsidering Bohr's Reply to EPR H. Halvorson, R. Clifton. Bohr on Bell: A Proposed Reading of Bohr and Its Implications for Bell's Theorem M. Dickson. Bell, Bohm, and von Neumann: Some Philosophical Inequalities Concerning No-go Theorems and the Axiomatic Method M. Stoltzner. Part Two: Interpreting Quantum Theory. Why Quantum Theory? L. Hardy. Quantum Mechanics of the Electric Charge and Its Connection with the Problem of Interpretation of Quantum Mechanics A. Staruszkiewicz. Signal-Locality and Subquantum Information in Deterministic Hidden-Variables Theories A. Valentini. Remarks on Space-time and Locality in Everett's Interpretation G. Bacciagaluppi. art Three: Entanglement and Non-Locality. s Quantum Mechanics Non-Local? W.G. Unruh. Measuring Quantum Entanglement L. Henderson. On Fine's Interpretation of Quantum Mechanics: GHZ Experiment L.E. Szabo. Locality and Reality Revisited A. Kent. Part Four: Unsharp Observables. EPR-Bell Tests with Unsharp Observables and Relativistic Quantum Measurement P. Busch. A Kochen-Specker Theorem for Unsharp Spin 1 Observables T. Breuer. The Bell Phenomenon in a Probabilistic Approach E.G. Beltrametti, S. Bugajski. Part Five: Causation. Non-locality and Theories of Causation F. Laudisa. On Causal Loops in the Quantum Realm J. Berkovitz. Reichenbach's Common Cause Principle and Quantum Correlations M. Redei. Part Six: Branching Models of EPR Phenomena. Branching Space-Time, Modal Logic and the Counterfactual Conditional T. Muller. EPR-like 'Funny Business' inthe Theory of Branching Space-times N. Belnap. Partial Indeterminism Is Enough: a Branching Analysis of Bell-type Inequalities T. Placek. Subject Index. Index of Names. more...
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- 2002
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12. The Vindication of Lorentz
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William Lane Craig
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De Broglie–Bohm theory ,symbols.namesake ,Theoretical physics ,Theory of relativity ,Lorentz transformation ,Philosophy ,Absolute time and space ,symbols ,Time dilation ,Motion (physics) ,Reference frame ,Length contraction - Abstract
In Newton’s view absolute time, God’s time, is the seat of temporal becoming and objective tense. The A-theorist may concur with Newton on this point, seeing SR as nothing more than a theory about relative time, that is, our physical measures of time. But how, then, does A-theoretic time connect with physical time? Given our rejection of the relativity interpretation of SR, it follows from the reality of tense that a Lorentzian theory of relativity is correct after all. The A-theorist may plausibly contend that that reference frame whose associated time coincides with and thus constitutes the measure of metaphysical time is thereby privileged and that the familiar relativistic phenomena are the result of motion relative to this frame. more...
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- 2000
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13. What John von Neumann Thought of the Bohm Interpretation
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Michael Stöltzner
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Cognitive science ,De Broglie–Bohm theory ,Computer Science::Information Retrieval ,Philosophy ,Interpretations of quantum mechanics ,Epistemology ,symbols.namesake ,Quantum state ,symbols ,Ontology ,Criticism ,Wave function collapse ,Naïve realism ,Von Neumann architecture - Abstract
Papers advocating a hidden-variable interpretation of quantum mechanics typically begin by emphasizing that John von Neumann’s no-go theorem does not apply to them. If authors are ontologically minded, their criticism also takes aim at his theory of measurement as expressed in his seminal 1932 book Mathematical Foundations of Quantum Mechanics Additionally, David Bohm and Basil Hiley have recently argued that “in so far as von Neumann effectively gave the quantum state a certain ontological significance, the net result was to produce a confused and unsatisfactory ontology. This ontology is such that the collapse of the wave function must also have an ontological significance.”1 more...
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- 1999
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14. Violation of Bell’s inequality in quantum field theory
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Miklós Rédei
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Physics ,Theoretical physics ,Bell state ,De Broglie–Bohm theory ,Local hidden variable theory ,Principle of locality ,Quantum mechanics ,CHSH inequality ,High Energy Physics::Experiment ,Bell test experiments ,Quantum entanglement ,Interpretations of quantum mechanics - Abstract
The aim of this chapter is to review some results obtained in the past decade on the violation of Bell’s inequality in algebraic relativistic quantum field theory (ARQFT).
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- 1998
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15. A Geometric Approach to the Quantum Mechanics of de Broglie and Vigier
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Giorgio Papini and W. R. Wood
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Physics ,Physics::General Physics ,De Broglie–Bohm theory ,Pilot wave ,010308 nuclear & particles physics ,Old quantum theory ,Quantum non-equilibrium ,Interpretations of quantum mechanics ,01 natural sciences ,Schrödinger equation ,symbols.namesake ,Wave–particle duality ,Classical mechanics ,Quantum mechanics ,0103 physical sciences ,symbols ,Matter wave ,010306 general physics - Abstract
Following de Broglie and Vigier, a fully relativistic causal interpretation of quantum mechanics is given within the context of a geometric theory of gravitation and electromagnetism. While the geometric model shares the essential principles of the causal interpretation initiated by de Broglie and advanced by Vigier, the particle and wave components of the theory are derived from the Einstein equations rather than a nonlinear wave equation. This geometric approach leads to several new features, including a solution to the de Broglie variable mass problem. more...
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- 1997
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16. Naive Realism about Operators
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Detlef Dürr, Nino Zanghì, Martin Daumer, and Sheldon Goldstein
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Consistent histories ,De Broglie–Bohm theory ,Observable ,06 humanities and the arts ,Interpretations of quantum mechanics ,0603 philosophy, ethics and religion ,01 natural sciences ,Physics::History of Physics ,Minority interpretations of quantum mechanics ,Quantum nonlocality ,symbols.namesake ,060302 philosophy ,0103 physical sciences ,symbols ,Calculus ,010306 general physics ,Naïve realism ,Schrödinger's cat ,Mathematics - Abstract
A source of much difficulty and confusion in the interpretation of quantum mechanics is a “naive realism about operators.” By this we refer to various ways of taking too seriously the notion of operator-as-observable, and in particular to the all too casual talk about “measuring operators” that occurs when the subject is quantum mechanics. Without a specification of what should be meant by “measuring” a quantum observable, such an expression can have no clear meaning. A definite specification is provided by Bohmian mechanics, a theory that emerges from Schrodinger's equation for a system of particles when we merely insist that “particles” means particles. Bohmian mechanics clarifies the status and the role of operators as observables in quantum mechanics by providing the operational details absent from standard quantum mechanics. It thereby allows us to readily dismiss all the radical claims traditionally enveloping the transition from the classical to the quantum realm — for example, that we must abandon classical logic or classical probability. The moral is rather simple: Beware naive realism, especially about operators! more...
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- 1997
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17. Pilot-Wave Theory of Fields, Gravitation and Cosmology
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Antony Valentini
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Physics ,Gravitation ,De Broglie–Bohm theory ,Parameterized post-Newtonian formalism ,Quantum nonlocality ,Uncertainty principle ,Classical mechanics ,Theory of relativity ,Quantum cosmology ,Classical field theory - Abstract
Our universe is characterised by: (i) The absence of practical instantaneous signals (signal-locality), and (ii) An all-pervading statistical ‘noise’ (uncertainty principle). Now, as Bell deduced, there is a fundamental nonlocality hidden behind quantum statistics. Relativity is not overtly violated, however. There seems to be a ‘conspiracy’ between relativity and quantum theory, whereby uncertainty noise prevents one from using subquantum nonlocality for practical signalling. Why should the nonlocality be hidden in this way? A physics whose coherence rests on such a peculiar conspiracy can hardly be regarded as fundamental. more...
- Published
- 1996
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18. Bohmian Mechanics and Quantum Theory: An Appraisal
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Sheldon Goldstein, Arthur Fine, and James T. Cushing
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Physics ,Consistent histories ,Quantum nonlocality ,Minority interpretations of quantum mechanics ,De Broglie–Bohm theory ,Classical mechanics ,Quantum mechanics ,Matter wave ,Quantum field theory ,Interpretations of quantum mechanics ,Kochen–Specker theorem - Abstract
Preface. I: Bohmian Mechanics: Background and Fundamentals. 1. The Causal Quantum Theory Program J.T. Cushing. 2. Bohmian Mechanics as the Foundation of Quantum Mechanics D. Durr, et al. 3. Pilot-Wave Theory of Fields, Gravitation and Cosmology A. Valentini. 4. Contextuality in Bohmian Mechanics L. Hardy. 5. Global Existence and Uniqueness of Bohmian Trajectories K. Berndl. 6. Scattering Theory from a Bohmian Perspective M. Daumer. 7. Is Quantum Mechanics Universal? P.R. Holland. II: Applications and Further Developments of Bohmian Mechanics. 8. The `Tunneling-Time Problem' for Electrons C.R. Leavens. 9. Local Bohmian Mechanics E.J. Squires. 10. About Position Measurements Which Do Not Show the Bohmian Particle Position Y. Aharonov, L. Vaidman. 11. An Ontological Interpretation of Boson Fields P.N. Kaloyerou. 12. De Broglie, Bohm and the Boson C. Dewdney, G. Horton. 13. A Realistic Formulation of Quantum Field Theory T.M. Samols. 14. Attaching Theories of Consciousness to Bohmian Quantum Mechanics D.N. Page. III: Historical, Conceptual and Philosophical Perspectives Related to Bohmian Mechanics. 15. Bohm and the `Inevitability' of Acausality M. Beller. 16. On the Interpretation of Bohmian Mechanics A. Fine. 17. Tension in Bohm's Interpretation of Quantum Mechanics M. Baublitz, A. Shimony. 18. An Epistemological Critique of Bohmian Mechanics R. Collins.19. Elementary Quantum Metaphysics D.Z. Albert. 20. Space-Time in the Quantum World T. Maudlin. 21. Cause and Effect in the Pilot-Wave Interpretation of Quantum Mechanics H.R. Brown, et al. 22. Is the Bohm Theory Local? M. Dickson. IV: Comparisons with Some Other Programs. 23. Modal Interpretations and Bohmian Mechanics J. Bub. 24. Remarks on Consistent Histories and Bohmian Mechanics A. Kent. 25. Bohm' Theory Versus Dynamical Reduction G.-C. Ghirardi, R. Grassi. Bibliography. The Authors. Index. more...
- Published
- 1996
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19. Local Bohmian Mechanics
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Euan J. Squires
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Physics ,De Broglie–Bohm theory ,Classical mechanics ,Simple (abstract algebra) ,Quantum potential ,Wave function - Abstract
A derivation of the Bohm model is given and some general observations are made about it. A local modification of the model is introduced and, for a simple experiment, its properties are studied.
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- 1996
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20. The 'Tunneling-Time Problem' for Electrons
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C. Richard Leavens
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De Broglie–Bohm theory ,Dwell time ,Free particle ,Extension (metaphysics) ,Classical mechanics ,Section (archaeology) ,Probability current ,Rectangular potential barrier ,Quantum clock ,Mathematics - Abstract
The very concept of the motion of an electron during the time interval between its preparation in a given state and the subsequent “collapse” of the time-evolved state during a measurement is widely regarded as a meaningless one within conventional quantum mechanics. Despite this, a large number of theoretical papers, including several reviews (e.g., Hauge and Stovneng 1989; Landauer and Martin 1994), have been devoted to various characteristic times associated with the motion of a particle interacting with a potential barrier. Most of the approaches involve, at least implicitly, some relatively straightforward extension of the fundamental postulates of standard quantum theory. These will be referred to as “conventional” approaches to distinguish them from those based on alternatives to quantum theory, such as Bohmian mechanics. In this paper, the approach based on Bohm’s theory is compared to several “conventional” methods that do not involve such radical departures from orthodoxy. In section 2, the characteristic times of interest are defined in words and the underlying reason for the difficulty in translating these words into unique, universally accepted mathematical expressions discussed. In Section 3, Bohmian mechanics is applied to the derivation of expressions for the mean dwell, transmission, reflection and arrival times. The systematic projector approach of Brouard et al. (1994) is considered in Section 4 where it is shown that none of the infinite number of possibilities for the mean transmission time that are generated by this method can be equal to the (unique) result from Bohmian mechanics. In Section 5, “conventional” probability current approaches are criticized from the point of view of Bohm’s theory. In Section 6, the quantum clock of Salecker and Wigner (1958) is applied to the calculation of the mean and mean-square dwell time. The results for the free particle case (no barrier) are particularly illuminating. Concluding remarks are made in Section 7. more...
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- 1996
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21. On the Interpretation of Bohmian Mechanics
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Arthur Fine
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symbols.namesake ,De Broglie–Bohm theory ,Minority interpretations of quantum mechanics ,Observer (quantum physics) ,Quantum mechanics ,Stochastic interpretation ,symbols ,Interpretations of quantum mechanics ,Indeterminism ,Complementarity (physics) ,Bohr model ,Epistemology - Abstract
Terms like “complementarity,” “potentia,” the “collapse” of the wave packet, “phenomena” identified with the whole experimental arrangement, and so forth, mark the standard interpretation of quantum mechanics. Despite different public faces there is a core unifying theme. The theory is probabilistic and, in contrast with statistical mechanics, the standard interpretation regards the probabilities as objective, in the sense that it does not ground them in human limitations concerning knowledge of the finer details of things. The objectivity of the probabilities makes for indeterminism and, more fundamentally, for some sort of irrealism; since, according to the standard view, in significant situations there just are no finer details of things. The irreducibility of the probabilities might be thought to constitute a realism of a higher order (with respect to the probabilities themselves) except that in the standard interpretation the probabilities are entirely instrumental. They express a relation between a physical system and acts of measurement; they are probabilities for measurement outcomes. Thus, in a curious turn about, despite the objectivity of the probabilities the observer enters quantum theory in a fundamental way. On Bohr’s view we are required to divide each experimental situation into an observer part, that is treated classically and to which we do not apply the quantum formalism, and a quantum part, to which we do. On Heisenberg’s view the probabilities in the wave function somehow objectively represent both real “potentialities” and also subjective knowledge. Standing outside the causal order, an act of measurement “actualizes” a potentiality and, when we take account of this actualization, our changing knowledge is again objectively represented by a new “collapsed” wave function. Either view makes a mystery of how any object ever comes to possess any property; that is, of how anything at all actually happens. Standardly, we are cautioned not to inquire further. Physics stops here. more...
- Published
- 1996
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22. Contextuality in Bohmian Mechanics
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Lucien Hardy
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De Broglie–Bohm theory ,Classical mechanics ,Wave packet ,Hidden variable theory ,Operator (physics) ,Context (language use) ,Quantum Physics ,Physics::History of Physics ,Mathematics ,Kochen–Specker theorem - Abstract
The Kochen—Specker theorem shows that noncontextual hidden variable interpretations of quantum theory are impossible. This does not mean, however, that hidden variable theories are not possible. In fact, the Bohm model is just such a theory. We show by considering an example involving interferometers how the Bohm model is contextual, thus circumventing the Kochen—Specker theorem. We will find that the result of a measurement of an operator in Bohmian mechanics is not just dependent on the context of other measurements that are also being performed at the same time, but also dependent on the way in which a particular measurement is performed. more...
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- 1996
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23. Remarks on Consistent Histories and Bohmian Mechanics
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Adrian Kent
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Consistent histories ,Physics ,De Broglie–Bohm theory ,Many-worlds interpretation ,Quantum probability ,Minority interpretations of quantum mechanics ,Classical mechanics ,Quantum gravity ,Interpretations of quantum mechanics ,Copenhagen interpretation ,Mathematical economics - Abstract
A distressing feature of discussions of the problems of quantum theory is their tendency to transform physicists from thoughtful and sophisticated scientific critics into uncomplicated partisans or unsympathetic spectators. This holds true although the most interesting questions posed by the various formulations of quantum theory, and by rival theories, are precisely the type of scientific and technical problems which physicists are trained to address. What, for example, does any given theory or formulation allow us to predict or infer, and from what data? Which of these predictions and inferences can be tested? How precise is the mathematical formulation, and what mathematical properties does it have? To what extent is it consistent with important physical principles such as invariance under Lorentz or general coordinate transformations? How elegantly is the theory formulated? On how many arbitrary quantities does it depend? more...
- Published
- 1996
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24. Elementary Quantum Metaphysics
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David Z Albert
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Physics ,De Broglie–Bohm theory ,Theoretical physics ,Metaphysics ,Configuration space ,Wave function ,Quantum - Abstract
Once upon a time, the twentieth-century investigations of the behaviors of sub-atomic particles were thought to have established that there can be no such thing as an objective, observer-independent, scientifically realist, empirically adequate picture of the physical world. more...
- Published
- 1996
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25. Tension in Bohm’s Interpretation of Quantum Mechanics
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Millard Baublitz and Abner Shimony
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Value (ethics) ,De Broglie–Bohm theory ,media_common.quotation_subject ,Philosophy ,Stochastic interpretation ,Interpretations of quantum mechanics ,Epistemology ,symbols.namesake ,Classical mechanics ,Explication ,symbols ,Born rule ,EPR paradox ,Skepticism ,media_common - Abstract
David Bohm and his predecessor Louis de Broglie (1927) were exploratory men, each of whom proposed and examined a number of theories. Their various theories shared some central ideas but also differed in significant respects, and an assessment of all of these variant theories is beyond the scope of this paper. We shall mainly restrict our attention to what we shall call “Rohm’s initial theory,” which was presented in his pioneering papers (Bohm 1952a,b), and in two letters (Bohm 1952c; 1953a) and a paper (Bohm 1953b) which clarified and defended his initial presentation. Our main thesis is that two different physical views coexist uneasily in Bohm’s initial theory, which we shall call “the causal view” and “the guidance view.” We shall cite passages indicating that he was aware of this fact and that he pondered ways of relieving the tension between the two views. Because of the great historical importance of Bohm’s initial theory, there is obviously value in a careful explication de texte. In addition, however, we have a conceptual thesis: that what makes Bohm’s initial theory attractive philosophically and scientifically is a conjunction of some features of the causal view and some of the guidance view. We shall present some reasons for skepticism about the prospects for a coherent combination of the two views. We shall also note that some of the most influential advocates of Bohmian mechanics — including Durr et al. (1992a), Valentini (1991a), and Cushing (1994) — treat the tension between the two views in the initial theory of Bohm by surgery, for they retain the guidance view and discard whatever of the causal view is incompatible with it. We shall not undertake to assess these recent expositions of Bohmian mechanics, because of mathematical difficulties which we find very formidable, but we shall express some skeptical doubts in hope of evoking clarifications and amplifications from the authors. more...
- Published
- 1996
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26. An Epistemological Critique of Bohmian Mechanics
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Robin Collins
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De Broglie–Bohm theory ,Theoretical physics ,Observable ,Ontological commitment ,Principle of sufficient reason ,Epistemology ,Mathematics - Abstract
In this paper, I argue that, as currently developed, Bohm’s theory does not provide a better explanation of observable phenomena than a phenomenalist account of quantum mechanics, that is, an account that merely takes the phenomenological laws of quantum mechanics as its unexplained given. Thus, by a version of Ockam’s razor, I conclude that we do not have sufficient reason to believe that Bohm’s theory is (approximately) true — that is, that it provides a basically correct account of the way the world is. Although not everyone interested in Bohm’s theory is concerned with its truth, it is an issue that should be of concern to those trying to understand what quantum mechanics tells us about the nature of the world. more...
- Published
- 1996
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27. Scattering Theory from a Bohmian Perspective
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Martin Daumer
- Subjects
Physics ,Minority interpretations of quantum mechanics ,De Broglie–Bohm theory ,Classical mechanics ,Scattering ,Quantum Physics ,Scattering theory ,D'Alembert operator ,Wave function ,Quantum ,S-matrix - Abstract
Quantum mechanical scattering theory is a subject with a long and winding history. We shall pick out some of the most important concepts and ideas of scattering theory and look at them from the perspective of Bohmian mechanics: Bohmian mechanics, having real particle trajectories, provides an excellent basis for analyzing scattering phenomena. more...
- Published
- 1996
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28. A Realistic Formulation of Quantum Field Theory
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Trevor M. Samols
- Subjects
Open quantum system ,Quantum probability ,Quantization (physics) ,De Broglie–Bohm theory ,Classical mechanics ,Thermal quantum field theory ,Quantum gravity ,Quantum field theory ,Quantum dissipation ,Physics::History of Physics ,Mathematics - Abstract
Bohm’s work has shown that it is possible to give a precise, realistic account of quantum theory. In his formulation, no recourse is made to ill-defined notions of “observation” or “measurement”, and the relation to classical mechanics is unproblematic, the latter simply being a good approximation to the “true” (Bohmian) dynamics under certain precisely definable conditions. more...
- Published
- 1996
- Full Text
- View/download PDF
29. Modal Interpretations and Bohmian Mechanics
- Author
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Jeffrey Bub
- Subjects
Minority interpretations of quantum mechanics ,De Broglie–Bohm theory ,Theoretical physics ,Quantum state ,Truth value ,Transition of state ,Observable ,Interpretations of quantum mechanics ,Quantum ,Mathematics - Abstract
The idea behind a ‘modal’ interpretation of quantum mechanics is that quantum states, unlike classical states, constrain possibilities rather than actualities — which leaves open the question of whether one can introduce ‘value states’ (van Fraassen 1991, 275) that assign values to the dynamical variables or ‘observables’ of the theory, or equivalently, truth values to the corresponding propositions. As van Fraassen (1991, 279) puts it: In other words, the [quantum] state delimits what can and cannot occur, and how likely it is — it delimits possibility, impossibility, and probability of occurrence — but it does not say what actually occurs. The transition from the possible to the actual is not a transition of state, but a transition described by the state. more...
- Published
- 1996
- Full Text
- View/download PDF
30. Is the Bohm Theory Local?
- Author
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Michael Dickson
- Subjects
Physics::General Physics ,De Broglie–Bohm theory ,Classical mechanics ,Laplace transform ,Light cone ,Newtonian fluid ,Deterministic theory ,Demon ,Physics::History of Physics ,Mathematics ,Functional relation - Abstract
Technicalities aside, Newtonian mechanics is a fully deterministic theory. This fact prompted Laplace’s vision of a world whose evolution could be predicted with complete accuracy by a sufficiently powerful demon using only initial conditions and Newton’s laws. Forgoing the demon: in a Newtonian world, initial conditions fix everything.1 more...
- Published
- 1996
- Full Text
- View/download PDF
31. The Ontological Interpretation of Quantum Field Theory Applied in a Cosmological Context
- Author
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A. H. Aziz Muft and Basil J. Hiley
- Subjects
Physics ,Inflation (cosmology) ,General Relativity and Quantum Cosmology ,De Broglie–Bohm theory ,Classical mechanics ,De Sitter universe ,Quantum gravity ,Interpretations of quantum mechanics ,Quantum dissipation ,Relationship between string theory and quantum field theory ,Relational quantum mechanics - Abstract
In this paper it will be shown how the ontological (Bohm) interpretation of quantum field theory can be applied to the Guth-Pi model of the inflationary universe in a de Sitter spacetime. The Bohm interpretation has the advantage of providing a simple way of discussing the transition between the quantum and classical levels and thus we are able to demonstrate in a straight forward manner how the classical world emerges from the quantum origins of this specific model universe. more...
- Published
- 1995
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32. Underdetermination, Conventionalism and Realism: The Copenhagen vs. the Bohm Interpretation of Quantum Mechanics
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James T. Cushing
- Subjects
Physics ,Minority interpretations of quantum mechanics ,symbols.namesake ,De Broglie–Bohm theory ,Conventionalism ,Quantum mechanics ,symbols ,Correspondence principle ,Scientific theory ,Copenhagen interpretation ,Underdetermination ,Bohr model - Abstract
In an article from which the present Festschrift takes its title (Post 1971), Heinz Post discusses heuristic strategies with the aid of which scientists generate a successor (or more general, covering) theory L from a theory S that has been pressed beyond the limits of its validity. These “‘theoretic’ guide lines to new theories” (ibid., p. 217) he broadly classifies as invariance principles and a General Correspondence Principle (ibid., p. 228). Our comments here and this paper in general are related most directly to his correspondence principle, one feature of which consists in conserving in L, not only the successful empirical consequences of S,but also as many of the explanatorily useful and conceptually desirable features of S as possible, as well as requiring the new theory L to yield the old one S as a well-defined (mathematical and, perhaps, even conceptual) limit as some relevant parameter or physically significant quantity is varied. It is certainly true that both Bohr and Bohml used such heuristic guidelines to generate quantum mechanics from classical mechanics. Post claims (and quite correctly, as general characteristics of theory construction) that the procedure of generating a new theory (or of generalizing and old one) “is conservative (as every good scientist is).” (ibid.,p. 218). more...
- Published
- 1993
- Full Text
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33. The Dynamical Reduction Program
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GianCarlo Ghirardi
- Subjects
De Broglie–Bohm theory ,Objective property ,Observer (quantum physics) ,Computer science ,Conscious perception ,Wave packet ,Hidden variable theory ,Calculus ,Individual level - Abstract
The expression the “Dynamical Reduction Program (DRP)” is used here to denote some recent attempts to overcome the conceptual difficulties met by quantum mechanics (in particular in connection with measurement processes), by considering the possibility of modifying the linear evolution law of the theory. Such modifications should allow the derivation of wave packet reduction (WPR) at the individual level in “measurement like situations”, as a consequence of a unique fundamental dynamical principle governing all natural phenomena. From a conceptual point of view the adoption of the DRP corresponds to recognize that WPR actually occurs (and as such it implies to disregard attempts like the hidden variables approach or the many universes or many minds interpretations), but to pretend that it is a physical process occurring under appropriate and precisely defined physical circumstances. As such it does not require the act of conscious perception by an observer to play any fundamental role. more...
- Published
- 1992
- Full Text
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34. Quantum Measurement and Bell’s Theorem
- Author
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Henry Krips
- Subjects
De Broglie–Bohm theory ,Theoretical physics ,symbols.namesake ,Local hidden variable theory ,Bell's theorem ,Quantum mechanics ,symbols ,Bell test experiments ,Einstein ,Quantum indeterminacy ,Kochen–Specker theorem ,Mathematics ,No-communication theorem - Abstract
The concept of measurement favoured by Einstein, Bohm, Putnam, et al. in the context of Quantum Theory (QT) is a realist concept. It encapsulates the realist idea that in measurement we are about the task of reporting an independently existing objective reality. Moreover for Einstein, Bohm, Putnam et al. this objective reality is to be characterised classically in terms of physical quantities possessing particular values.1 Thus an “ideal measurement” is characterised as a process in which a measured value for some physical quantity is produced and that measured value reflects the value possessed by the physical quantity. more...
- Published
- 1987
- Full Text
- View/download PDF
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