The Ontological Basis of Quantum Theory, Nonlocality and Local Realism
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Accommodating Retrocausality with Free Will Yakir Aharonov Chapman University, [email protected]
Chapman University Chapman University Digital Commons Mathematics, Physics, and Computer Science Science and Technology Faculty Articles and Faculty Articles and Research Research 2016 Accommodating Retrocausality with Free Will Yakir Aharonov Chapman University, [email protected] Eliahu Cohen Tel Aviv University Tomer Shushi University of Haifa Follow this and additional works at: http://digitalcommons.chapman.edu/scs_articles Part of the Quantum Physics Commons Recommended Citation Aharonov, Y., Cohen, E., & Shushi, T. (2016). Accommodating Retrocausality with Free Will. Quanta, 5(1), 53-60. doi:http://dx.doi.org/10.12743/quanta.v5i1.44 This Article is brought to you for free and open access by the Science and Technology Faculty Articles and Research at Chapman University Digital Commons. It has been accepted for inclusion in Mathematics, Physics, and Computer Science Faculty Articles and Research by an authorized administrator of Chapman University Digital Commons. For more information, please contact [email protected]. Accommodating Retrocausality with Free Will Comments This article was originally published in Quanta, volume 5, issue 1, in 2016. DOI: 10.12743/quanta.v5i1.44 Creative Commons License This work is licensed under a Creative Commons Attribution 3.0 License. This article is available at Chapman University Digital Commons: http://digitalcommons.chapman.edu/scs_articles/334 Accommodating Retrocausality with Free Will Yakir Aharonov 1;2, Eliahu Cohen 1;3 & Tomer Shushi 4 1 School of Physics and Astronomy, Tel Aviv University, Tel Aviv, Israel. E-mail: [email protected] 2 Schmid College of Science, Chapman University, Orange, California, USA. E-mail: [email protected] 3 H. H. Wills Physics Laboratory, University of Bristol, Bristol, UK. -
Arxiv:1707.06910V2 [Physics.Hist-Ph] 22 Feb 2018 Xlntoscnenn H Eei Ftebte-Nw Pa Better-Known the of Genesis D the Park’S Concerning Analyze Explanations I States
Twelve years before the quantum no-cloning theorem Juan Ortigoso∗ Instituto de Estructura de la Materia, CSIC, Serrano 121, 28006 Madrid, Spain (Dated: January 22, 2018) Abstract The celebrated quantum no-cloning theorem establishes the impossibility of making a perfect copy of an unknown quantum state. The discovery of this important theorem for the field of quantum information is currently dated 1982. I show here that an article published in 1970 [J. L. Park, Foundations of Physics, 1, 23-33 (1970)] contained an explicit mathematical proof of the impossibility of cloning quantum states. I analyze Park’s demonstration in the light of published explanations concerning the genesis of the better-known papers on no-cloning. arXiv:1707.06910v2 [physics.hist-ph] 22 Feb 2018 1 I. INTRODUCTION The no-cloning theorem of quantum mechanics establishes that an arbitrary unknown quantum state cannot be copied.1 A modern proof,2 based on the linearity of quantum mechanics, takes two lines. Suppose that a device can implement a transformation T for copying two orthogonal states ψ and φ of a qubit: T ψ 0 = ψ ψ and T φ 0 = φ φ , | i | i | i| i | i| i | i| i | i| i where 0 is the ready state of the target system. It follows, from linearity, that | i T (a ψ + b φ ) 0 = aT ψ 0 + bT φ 0 = a ψ ψ + b φ φ . (1) | i | i | i | i| i | i| i | i| i | i| i But if the transformation T can clone arbitrary states, it should give, for any a, b values T (a ψ +b φ ) 0 =(a ψ +b φ )(a ψ +b φ )= a2 ψ ψ +b2 φ φ +ab ψ φ +ab φ ψ , (2) | i | i | i | i | i | i | i | i| i | i| i | i| i | i| i which is different from Eq. -
1 Electromagnetic Fields and Charges In
Electromagnetic fields and charges in ‘3+1’ spacetime derived from symmetry in ‘3+3’ spacetime J.E.Carroll Dept. of Engineering, University of Cambridge, CB2 1PZ E-mail: [email protected] PACS 11.10.Kk Field theories in dimensions other than 4 03.50.De Classical electromagnetism, Maxwell equations 41.20Jb Electromagnetic wave propagation 14.80.Hv Magnetic monopoles 14.70.Bh Photons 11.30.Rd Chiral Symmetries Abstract: Maxwell’s classic equations with fields, potentials, positive and negative charges in ‘3+1’ spacetime are derived solely from the symmetry that is required by the Geometric Algebra of a ‘3+3’ spacetime. The observed direction of time is augmented by two additional orthogonal temporal dimensions forming a complex plane where i is the bi-vector determining this plane. Variations in the ‘transverse’ time determine a zero rest mass. Real fields and sources arise from averaging over a contour in transverse time. Positive and negative charges are linked with poles and zeros generating traditional plane waves with ‘right-handed’ E, B, with a direction of propagation k. Conjugation and space-reversal give ‘left-handed’ plane waves without any net change in the chirality of ‘3+3’ spacetime. Resonant wave-packets of left- and right- handed waves can be formed with eigen frequencies equal to the characteristic frequencies (N+½)fO that are observed for photons. 1 1. Introduction There are many and varied starting points for derivations of Maxwell’s equations. For example Kobe uses the gauge invariance of the Schrödinger equation [1] while Feynman, as reported by Dyson, starts with Newton’s classical laws along with quantum non- commutation rules of position and momentum [2]. -
Arxiv:2002.00255V3 [Quant-Ph] 13 Feb 2021 Lem (BVP)
A Path Integral approach to Quantum Fluid Dynamics Sagnik Ghosh Indian Institute of Science Education and Research, Pune-411008, India Swapan K Ghosh UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Kalina, Santacruz, Mumbai-400098, India ∗ (Dated: February 16, 2021) In this work we develop an alternative approach for solution of Quantum Trajectories using the Path Integral method. The state-of-the-art technique in the field is to solve a set of non-linear, coupled partial differential equations (PDEs) simultaneously. We opt for a fundamentally different route. We first derive a general closed form expression for the Path Integral propagator valid for any general potential as a functional of the corresponding classical path. The method is exact and is applicable in many dimensions as well as multi-particle cases. This, then, is used to compute the Quantum Potential (QP), which, in turn, can generate the Quantum Trajectories. For cases, where closed form solution is not possible, the problem is formally boiled down to solving the classical path as a boundary value problem. The work formally bridges the Path Integral approach with Quantum Fluid Dynamics. As a model application to illustrate the method, we work out a toy model viz. the double-well potential, where the boundary value problem for the classical path has been computed perturbatively, but the Quantum part is left exact. Using this we delve into seeking insight in one of the long standing debates with regard to Quantum Tunneling. Keywords: Path Integral, Quantum Fluid Dynamics, Analytical Solution, Quantum Potential, Quantum Tunneling, Quantum Trajectories Submitted to: J. -
Downloading Physics Preprints from Arxiv Would Be Quite Unaware That a Paper in General Physics Has to Be Treated Differently to Papers in Other Categories
1 The Ecology of Fringe Science and its Bearing on Policy Harry Collins, Andrew Bartlett and Luis Reyes-Galindo School of Social Sciences, Cardiff University1 emails: [email protected], [email protected], [email protected] Introduction Fringe science has been an important topic since the start of the revolution in the social studies of science that occurred in the early 1970s.2 As a softer-edged model of the sciences developed, fringe science was a ‘hard case’ on which to hammer out the idea that scientific truth was whatever came to count as scientific truth: scientific truth emerged from social closure. The job of those studying fringe science was to recapture the rationality of its proponents, showing how, in terms of the procedures of science, they could be right and the mainstream could be wrong and therefore the consensus position is formed by social agreement. One outcome of this way of thinking is that sociologists of science informed by the perspective outlined above find themselves short of argumentative resources for demarcating science from non-science. The distinction with traditional philosophy of science, which readily demarcates fringe subjects such as parapsychology by referring to their ‘irrationality’ or some such, is marked.3 For the sociologist of scientific knowledge, that kind of demarcation comprises 1 This paper is joint work by researchers supported by two grants: ESRC to Harry Collins, (RES/K006401/1) £277,184, What is scientific consensus for policy? Heartlands and hinterlands of physics (2014-2016); British Academy Post-Doctoral Fellowship to Luis Reyes-Galindo, (PF130024) £223,732, The social boundaries of scientific knowledge: a case study of 'green' Open Access (2013-2016). -
Retrocausality in Energetic Causal Sets Arxiv:1902.05082V3 [Gr-Qc]
Realism and Causality II: Retrocausality in Energetic Causal Sets Eliahu Cohen1, Marina Cortesˆ 2;3, Avshalom C. Elitzur4;5 and Lee Smolin3 1 Faculty of Engineering, Bar Ilan University, Ramat Gan 5290002, Israel 2 Instituto de Astrof´ısica e Cienciasˆ do Espac¸o Faculdade de Ciencias,ˆ 1769-016 Lisboa, Portugal 3 Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, Ontario N2J 2Y5, Canada 4 Iyar, The Israeli Institute for Advanced Research, POB 651, Zichron Ya’akov 3095303, Israel 5 Institute for Quantum Studies, Chapman University, Orange, CA 92866, USA November 3, 2020 Abstract We describe a new form of retrocausality, which is found in the behaviour of a class of causal set theories, called energetic causal sets (ECS). These are discrete sets of events, connected by causal relations. They have three orders: (1) a birth order, which is the order in which events are generated; this is a total order which is the true causal order, (2) a dynamical partial order, which prescribes the flows of energy and momen- tum amongst events, (3) an emergent causal order, which is defined by the geometry of an emergent Minkowski spacetime, in which the events of the causal sets are em- arXiv:1902.05082v3 [gr-qc] 1 Nov 2020 bedded. However, the embedding of the events in the emergent Minkowski spacetime may preserve neither the true causal order in (1), nor correspond completely with the microscopic partial order in (2). We call this disordered causality, and we here demon- strate its occurrence in specific ECS models. This is the second in a series of papers centered around the question: Should we accept violations of causality as a lesser price to pay in order to keep realist formula- tions of quantum theory? We begin to address this in the first paper [1] and continue here by giving an explicit example of an ECS model in the classical regime, in which causality is disordered. -
Simulation of the Bell Inequality Violation Based on Quantum Steering Concept Mohsen Ruzbehani
www.nature.com/scientificreports OPEN Simulation of the Bell inequality violation based on quantum steering concept Mohsen Ruzbehani Violation of Bell’s inequality in experiments shows that predictions of local realistic models disagree with those of quantum mechanics. However, despite the quantum mechanics formalism, there are debates on how does it happen in nature. In this paper by use of a model of polarizers that obeys the Malus’ law and quantum steering concept, i.e. superluminal infuence of the states of entangled pairs to each other, simulation of phenomena is presented. The given model, as it is intended to be, is extremely simple without using mathematical formalism of quantum mechanics. However, the result completely agrees with prediction of quantum mechanics. Although it may seem trivial, this model can be applied to simulate the behavior of other not easy to analytically evaluate efects, such as defciency of detectors and polarizers, diferent value of photons in each run and so on. For example, it is demonstrated, when detector efciency is 83% the S factor of CHSH inequality will be 2, which completely agrees with famous detector efciency limit calculated analytically. Also, it is shown in one-channel polarizers the polarization of absorbed photons, should change to the perpendicular of polarizer angle, at very end, to have perfect violation of the Bell inequality (2 √2 ) otherwise maximum violation will be limited to (1.5 √2). More than a half-century afer celebrated Bell inequality 1, nonlocality is almost totally accepted concept which has been proved by numerous experiments. Although there is no doubt about validity of the mathematical model proposed by Bell to examine the principle of the locality, it is comprehended that Bell’s inequality in its original form is not testable. -
Violation of Bell Inequalities: Mapping the Conceptual Implications
International Journal of Quantum Foundations 7 (2021) 47-78 Original Paper Violation of Bell Inequalities: Mapping the Conceptual Implications Brian Drummond Edinburgh, Scotland. E-mail: [email protected] Received: 10 April 2021 / Accepted: 14 June 2021 / Published: 30 June 2021 Abstract: This short article concentrates on the conceptual aspects of the violation of Bell inequalities, and acts as a map to the 265 cited references. The article outlines (a) relevant characteristics of quantum mechanics, such as statistical balance and entanglement, (b) the thinking that led to the derivation of the original Bell inequality, and (c) the range of claimed implications, including realism, locality and others which attract less attention. The main conclusion is that violation of Bell inequalities appears to have some implications for the nature of physical reality, but that none of these are definite. The violations constrain possible prequantum (underlying) theories, but do not rule out the possibility that such theories might reconcile at least one understanding of locality and realism to quantum mechanical predictions. Violation might reflect, at least partly, failure to acknowledge the contextuality of quantum mechanics, or that data from different probability spaces have been inappropriately combined. Many claims that there are definite implications reflect one or more of (i) imprecise non-mathematical language, (ii) assumptions inappropriate in quantum mechanics, (iii) inadequate treatment of measurement statistics and (iv) underlying philosophical assumptions. Keywords: Bell inequalities; statistical balance; entanglement; realism; locality; prequantum theories; contextuality; probability space; conceptual; philosophical International Journal of Quantum Foundations 7 (2021) 48 1. Introduction and Overview (Area Mapped and Mapping Methods) Concepts are an important part of physics [1, § 2][2][3, § 1.2][4, § 1][5, p. -
Revised Version, October, 2016
© <2016>. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ THE ORIGINS OF THE RESEARCH ON THE FOUNDATIONS OF QUANTUM MECHANICS (AND OTHER CRITICAL ACTIVITIES) IN ITALY DURING THE 1970s (Revised version, October, 2016) Angelo Baracca*, Silvio Bergia+ and Flavio Del Santo” * University of Florence, Italy, [email protected] + University of Bologna, Italy, [email protected] ― University of Vienna, Austria, [email protected] Abstract We present a reconstruction of the studies on the Foundations of Quantum Mechanics carried out in Italy at the turn of the 1960s. Actually, they preceded the revival of the interest of the American physicists towards the foundations of quantum mechanics around mid-1970s, recently reconstructed by David Kaiser in a book of 2011. An element common to both cases is the role played by the young generation, even though the respective motivations were quite different. In the US they reacted to research cuts after the war in Vietnam, and were inspired by the New Age mood. In Italy the dissatisfaction of the young generations was rooted in the student protests of 1968 and the subsequent labour and social fights, which challenged the role of scientists. The young generations of physicists searched for new scientific approaches and challenged their own scientific knowledge and role. The criticism to the foundations of quantum mechanics and the perspectives of submitting them to experimental tests were perceived as an innovative research field and this attitude was directly linked to the search for an innovative and radical approach in the history of science. -
Quantum Nonlocality Explained
Quantum Nonlocality Explained Ulrich Mohrhoff Sri Aurobindo International Centre of Education Pondicherry 605002 India [email protected] Abstract Quantum theory's violation of remote outcome independence is as- sessed in the context of a novel interpretation of the theory, in which the unavoidable distinction between the classical and quantum domains is understood as a distinction between the manifested world and its manifestation. 1 Preliminaries There are at least nine formulations of quantum mechanics [1], among them Heisenberg's matrix formulation, Schr¨odinger'swave-function formu- lation, Feynman's path-integral formulation, Wigner's phase-space formula- tion, and the density-matrix formulation. The idiosyncracies of these forma- tions have much in common with the inertial reference frames of relativistic physics: anything that is not invariant under Lorentz transformations is a feature of whichever language we use to describe the physical world rather than an objective feature of the physical world. By the same token, any- thing that depends on the particular formulation of quantum mechanics is a feature of whichever mathematical tool we use to calculate the values of observables or the probabilities of measurement outcomes rather than an objective feature of the physical world. That said, when it comes to addressing specific questions, some formu- lations are obviously more suitable than others. As Styer et al. [1] wrote, The ever-popular wavefunction formulation is standard for prob- lem solving, but leaves the conceptual misimpression that [the] wavefunction is a physical entity rather than a mathematical tool. The path integral formulation is physically appealing and 1 generalizes readily beyond the domain of nonrelativistic quan- tum mechanics, but is laborious in most standard applications. -
Spacetime Structuralism
Philosophy and Foundations of Physics 37 The Ontology of Spacetime D. Dieks (Editor) r 2006 Elsevier B.V. All rights reserved DOI 10.1016/S1871-1774(06)01003-5 Chapter 3 Spacetime Structuralism Jonathan Bain Humanities and Social Sciences, Polytechnic University, Brooklyn, NY 11201, USA Abstract In this essay, I consider the ontological status of spacetime from the points of view of the standard tensor formalism and three alternatives: twistor theory, Einstein algebras, and geometric algebra. I briefly review how classical field theories can be formulated in each of these formalisms, and indicate how this suggests a structural realist interpre- tation of spacetime. 1. Introduction This essay is concerned with the following question: If it is possible to do classical field theory without a 4-dimensional differentiable manifold, what does this suggest about the ontological status of spacetime from the point of view of a semantic realist? In Section 2, I indicate why a semantic realist would want to do classical field theory without a manifold. In Sections 3–5, I indicate the extent to which such a feat is possible. Finally, in Section 6, I indicate the type of spacetime realism this feat suggests. 2. Manifolds and manifold substantivalism In classical field theories presented in the standard tensor formalism, spacetime is represented by a differentiable manifold M and physical fields are represented by tensor fields that quantify over the points of M. To some authors, this has 38 J. Bain suggested an ontological commitment to spacetime points (e.g., Field, 1989; Earman, 1989). This inclination might be seen as being motivated by a general semantic realist desire to take successful theories at their face value, a desire for a literal interpretation of the claims such theories make (Earman, 1993; Horwich, 1982). -
On a Complex Spacetime Frame : New Foundation for Physics and Mathematics
On a complex spacetime frame : new foundation for physics and mathematics Joseph Akeyo Omolo∗ Department of Physics and Materials Science, Maseno University P.O. Private Bag, Maseno, Kenya e-mail: [email protected] March 31, 2016 Abstract This paper provides a derivation of a unit vector specifying the tem- poral axis of four-dimensional space-time frame as an imaginary axis in the direction of light or general wave propagation. The basic elements of the resulting complex four-dimensional spacetime frame are complex four-vectors expressed in standard form as four-component quantities specified by four unit vectors, three along space axes and one along the imaginary temporal axis. Consistent mathematical operations with the complex four-vectors have been developed, which provide extensions of standard vector analysis theorems to complex four-dimensional space- time. The general orientation of the temporal unit vector relative to all the three mutually perpendicular spatial unit vectors leads to ap- propriate modifications of fundamental results describing the invariant length of the spacetime event interval, time dilation, mass increase with speed and relativistic energy conservation law. Contravariant and co- variant forms have been defined, providing appropriate definition of the invariant length of a complex four-vector and appropriate definitions of complex tensors within the complex four-dimensional spacetime frame, thus setting a new geometrical framework for physics and mathematics. 1 Introduction Four-dimensional space-time frame is the natural reference frame for de- scribing the general dynamics of physical systems. Its basic elements are ∗Regular Associate, Abdus Salam ICTP: 2001-2006 1 four-vectors, which are suitable for expressing field equations and associ- ated physical quantities in consistent forms.