About this topic
Summary Traditional formulations of quantum mechanics rely on an unanalysed concept of measurement. Quantum systems are treated as evolving via the unitary Schrodinger evolution, except when they are measured or observed; then, all components of the state are discarded except the one corresponding to the actual measurement result. The component which remains is then regarded as the new state of the system and again is evolved forwards according to the unitary evolution. The measurement problem is the problem of explaining why this two-stage procedure employing a primitive concept of measurement works so well.
Key works Bell 2004 contains a number of exceptionally clear discussions of the measurement problem. Bohr 1935 contains the first explicit claim that measurement plays a fundamental role in quantum theory.
Introductions Albert 1992
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297 found
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  1. Why Decoherence has Not Solved the Measurement Problem: A Response to P.W. Anderson.Stephen L. Adler - 2003 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 34 (1):135-142.
  2. Why Decoherence has Not Solved the Measurement Problem: A Response to P.W. Anderson.Stephen L. Adler - 2003 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 34 (1):135-142.
  3. Many-Measurements or Many-Worlds? A Dialogue.Diederik Aerts & Massimiliano Sassoli de Bianchi - 2015 - Foundations of Science 20 (4):399-427.
    Many advocates of the Everettian interpretation consider that theirs is the only approach to take quantum mechanics really seriously, and that this approach allows to deduce a fantastic scenario for our reality, one that consists of an infinite number of parallel worlds that branch out continuously. In this article, written in dialogue form, we suggest that quantum mechanics can be taken even more seriously, if the many-worlds view is replaced by a many-measurements view. This allows not only to derive the (...)
  4. An Operational Approach for Testing the Postulate of Measurement in Quantum Theory.Y. Aharonov & M. Vardi - 1981 - Foundations of Physics 11 (1-2):121-125.
    We interpret the (formal) postulates of measurement in quantum theory in terms of measurement procedures that can be done in the laboratory (at least in principle).
  5. The Meaning of Protective Measurements.Yakir Aharonov, Jeeva Anandan & Lev Vaidman - 1996 - Foundations of Physics 26 (1):117-126.
    Protective measurement, which we have introduced recently, allows one to observe properties of the state of a single quantum system and even the Schrödinger wave itself. These measurements require a protection, sometimes due to an additional procedure and sometimes due to the potential of the system itself The analysis of the protective measurements is presented and it is argued, contrary to recent claims, that they observe the quantum state and not the protective potential. Some other misunderstandings concerning our proposal are (...)
  6. On the Phenomenology of Quantum-Mechanical Superpositions.D. Albert - 1997 - Poznan Studies in the Philosophy of the Sciences and the Humanities 55:196-215.
  7. Some Alleged Solutions to the Measurement Problem.D. Albert & B. Loewer - 1991 - Synthese 88:87-98.
  8. Quantum Mechanics and Experience.David Z. Albert - 1992 - Harvard Up.
  9. The Measurement Problem: Some “Solutions”.David Z. Albert & Barry Loewer - 1991 - Synthese 86 (1):87 - 98.
  10. How to Make Sense of Quantum Mechanics : Fundamental Physical Theories and Primitive Ontology.Valia Allori - manuscript
    Quantum mechanics has always been regarded as, at best, puzzling, if not contradictory. The aim of the paper is to explore a particular approach to fundamental physical theories, the one based on the notion of primitive ontology. This approach, when applied to quantum mechanics, makes it a paradox-free theory.
  11. Book Review of S. Gao "Protective Measurement and Quantum Reality". [REVIEW]Valia Allori - 2017 - British Journal for the Philosophy of Science:x-y.
  12. Primitive Ontology in a Nutshell.Valia Allori - 2015 - International Journal of Quantum Foundations 1 (2):107-122.
    The aim of this paper is to summarize a particular approach of doing metaphysics through physics - the primitive ontology approach. The idea is that any fundamental physical theory has a well-defined architecture, to the foundation of which there is the primitive ontology, which represents matter. According to the framework provided by this approach when applied to quantum mechanics, the wave function is not suitable to represent matter. Rather, the wave function has a nomological character, given that its role in (...)
  13. Primitive Ontology and the Structure of Fundamental Physical Theories.Valia Allori - 2013 - In Alyssa Ney & David Z. Albert (eds.), The Wave Function: Essays in the Metaphysics of Quantum Mechanics. Oxford University Press.
    For a long time it was believed that it was impossible to be realist about quantum mechanics. It took quite a while for the researchers in the foundations of physics, beginning with John Stuart Bell [Bell 1987], to convince others that such an alleged impossibility had no foundation. Nowadays there are several quantum theories that can be interpreted realistically, among which Bohmian mechanics, the GRW theory, and the many-worlds theory. The debate, though, is far from being over: in what respect (...)
  14. On the Metaphysics of Quantum Mechanics.Valia Allori - 2013 - In Soazig Lebihan (ed.), Precis de la Philosophie de la Physique. Vuibert.
    What is quantum mechanics about? The most natural way to interpret quantum mechanics realistically as a theory about the world might seem to be what is called wave function ontology: the view according to which the wave function mathematically represents in a complete way fundamentally all there is in the world. Erwin Schroedinger was one of the first proponents of such a view, but he dismissed it after he realized it led to macroscopic superpositions (if the wave function evolves in (...)
  15. Quantum Theory: A Philosopher's Overview. [REVIEW]Valia Allori - 2010 - International Studies in the Philosophy of Science 24 (3):330-333.
    Book review of "Quantum Theory: a Philosopher's Overview".
  16. Fundamental Physical Theories: Mathematical Structures Grounded on a Primitive Ontology.Valia Allori - 2007 - Dissertation, Rutgers
    In my dissertation I analyze the structure of fundamental physical theories. I start with an analysis of what an adequate primitive ontology is, discussing the measurement problem in quantum mechanics and theirs solutions. It is commonly said that these theories have little in common. I argue instead that the moral of the measurement problem is that the wave function cannot represent physical objects and a common structure between these solutions can be recognized: each of them is about a clear three-dimensional (...)
  17. Decoherence and the Classical Limit of Quantum Mechanics.Valia Allori - 2002 - Dissertation, University of Genova, Italy
    In my dissertation (Rutgers, 2007) I developed the proposal that one can establish that material quantum objects behave classically just in case there is a “local plane wave” regime, which naturally corresponds to the suppression of all quantum interference.
  18. Predictions and Primitive Ontology in Quantum Foundations: A Study of Examples.Valia Allori, Sheldon Goldstein, Roderich Tumulka & Nino Zanghi - 2012 - British Journal for the Philosophy of Science (2):axs048.
    A major disagreement between different views about the foundations of quantum mechanics concerns whether for a theory to be intelligible as a fundamental physical theory it must involve a ‘primitive ontology’ (PO), i.e. variables describing the distribution of matter in four-dimensional space–time. In this article, we illustrate the value of having a PO. We do so by focussing on the role that the PO plays for extracting predictions from a given theory and discuss valid and invalid derivations of predictions. To (...)
  19. E' completa la descrizione della realta' fisica fornita dalla meccanica quantistica?Valia Allori & Nino Zanghi - 2007 - Il Protagora 9:163-180.
    In this paper (in Italian) we discuss how quantum theories can be thought of as having the same structure. If so, even the theories that appear to be about the wave function are incomplete, even if in a way which is very different from the one Einstein proposed.
  20. What is Bohmian Mechanics.Valia Allori & Nino Zanghi - 2004 - International Journal of Theoretical Physics 43:1743-1755.
    Bohmian mechanics is a quantum theory with a clear ontology. To make clear what we mean by this, we shall proceed by recalling first what are the problems of quantum mechanics. We shall then briefly sketch the basics of Bohmian mechanics and indicate how Bohmian mechanics solves these problems and clarifies the status and the role of of the quantum formalism.
  21. Coordinate Transformations and the Theory of Measurement.Martin S. Altschul - 1978 - Foundations of Physics 8 (1-2):69-92.
    We discuss the criteria for deriving new information from coordinate transformations, focusing on the property of implementability, or measurability in practice. We contrast the role of coordinate transformations in classical and quantum physics, and demonstrate that many well-known applications fail to meet the criteria for new information. Finally, we discuss some mathematical properties of the coordinate transformations, and then relate these properties to a practical measurement scheme.
  22. Classical Versus Quantum Probability in Sequential Measurements.Charis Anastopoulos - 2006 - Foundations of Physics 36 (11):1601-1661.
    We demonstrate in this paper that the probabilities for sequential measurements have features very different from those of single-time measurements. First, they cannot be modelled by a classical stochastic process. Second, they are contextual, namely they depend strongly on the specific measurement scheme through which they are determined. We construct Positive-Operator-Valued measures (POVM) that provide such probabilities. For observables with continuous spectrum, the constructed POVMs depend strongly on the resolution of the measurement device, a conclusion that persists even if we (...)
  23. Barrett, Jeffrey Allan. The Quantum Mechanics of Minds and Worlds. [REVIEW]Aristidis Arageorgis - 2001 - Review of Metaphysics 54 (4):904-905.
  24. How to Discover That the Real is Unreal.Frank Arntzenius - 1993 - Erkenntnis 38 (2):191 - 202.
    The measurement problem in quantum mechanics is presented in a completely non-technical way by means of the results of some very simple experiments. These experimental results themselves, rather than the formalism of quantum theory, are shown to be extremely hard to incorporate in a sensible state-space picture of the world. A novel twist is then added which makes the problem even harder than it appears to be in other presentations of the measurement problem.
  25. O problema ontológico da consciência na mecânica quântica.Raoni Wohnrath Arroyo - 2015 - Dissertation, Universidade Estadual de Maringá
    Quantum mechanics is an area of Physics that deals with subatomic phenomena. It can be extracted from a vision of the physical world which contradicts many aspects of our everyday perception, prompting many philosophical debates and admitting different interpretations. Among the wide range of problems within the interpretation of quantum theory, there is the measurement problem. Some philosophical aspects of the problems concerning the notion of “measurement” in quantum mechanics are analyzed in order to identify how the problem arises in (...)
  26. The Aspect of Information Production in the Process of Observation.Harald Atmanspacher - 1989 - Foundations of Physics 19 (5):553-577.
    The physical process of observation is considered from a specific information theoretical viewpoint. Using the modified concept of an information based on infinite alternatives, a formalism is derived describing the elementary transfer of one bit of information. This bit of information is produced on a virtual (nonreal) sub-quantum level of physical description. The interpretation of the formalism yields the following, complementary points: (i) the effect of spatiotemporal delocalization on the sub-quantum level, and (ii) a possible access to the concept of (...)
  27. Quantum Information and Inferential Reasoning.Gennaro Auletta - 2005 - Foundations of Physics 35 (1):155-156.
    Information may be extracted from a quantum–mechanical system only by means of inference. For this reason, the observer, although not required as such for obtaining an eigenstate of the measured observable on a given system, is necessary for obtaining information.
  28. A Philosopher's View of the Epistemic Interpretation of Quantum Mechanics.Shahar Avin - unknown
    There are various reasons for favouring Ψ-epistemic interpretations of quantum mechanics over Ψ-ontic interpretations. One such reason is the correlation between quantum mechanics and Liouville dynamics. Another reason is the success of a specific epistemic model (Spekkens, 2007), in reproducing a wide range of quantum phenomena. The potential criticism, that Spekkens' restricted knowledge principle is counter-intuitive, is rejected using `everyday life' examples. It is argued that the dimensionality of spin favours Spekkens' model over Ψ-ontic models. van Enk's extension of Spekkens' (...)
  29. Insolubility Theorems and EPR Argument.Guido Bacciagaluppi - 2013 - European Journal for Philosophy of Science 3 (1):87-100.
    I present a very general and simple argument—based on the no-signalling theorem—showing that within the framework of the unitary Schrödinger equation it is impossible to reproduce the phenomenological description of quantum mechanical measurements (in particular the collapse of the state of the measured system) by assuming a suitable mixed initial state of the apparatus. The thrust of the argument is thus similar to that of the ‘insolubility theorems’ for the measurement problem of quantum mechanics (which, however, focus on the impossibility (...)
  30. Measurement and Classical Regime in Quantum Mechanics.Guido Bacciagaluppi - unknown
    This article focuses on two of the main problems raising interpretational issues in quantum mechanics, namely the notorious measurement problem and the equally important but not quite as widely discussed problem of the classical regime. The two problems are distinct, but they are both intimately related to some of the issues arising from entanglement and density operators. The article aims to be fairly non-technical in language, but modern in outlook and covering the chosen topics in more depth than most introductory (...)
  31. The Role of Decoherence in Quantum Mechanics.Guido Bacciagaluppi - 2008 - Stanford Encyclopedia of Philosophy.
    Interference phenomena are a well-known and crucial feature of quantum mechanics, the two-slit experiment providing a standard example. There are situations, however, in which interference effects are (artificially or spontaneously) suppressed. We shall need to make precise what this means, but the theory of decoherence is the study of (spontaneous) interactions between a system and its environment that lead to such suppression of interference. This study includes detailed modelling of system-environment interactions, derivation of equations (‘master equations’) for the (reduced) state (...)
  32. Five Formulations of the Quantum Measurement Problem in the Frame of the Standard Interpretation.Manuel Bächtold - 2008 - Journal for General Philosophy of Science / Zeitschrift für Allgemeine Wissenschaftstheorie 39 (1):17-33.
    The aim of this paper is to give a systematic account of the so-called “measurement problem” in the frame of the standard interpretation of quantum mechanics. It is argued that there is not one but five distinct formulations of this problem. Each of them depends on what is assumed to be a “satisfactory” description of the measurement process in the frame of the standard interpretation. Moreover, the paper points out that each of these formulations refers not to a unique problem, (...)
  33. Beyond Measure: Modern Physics, Philosophy, and the Meaning of Quantum Theory.J. E. Baggott - 2003 - Oxford University Press.
    Quantum theory is one the most important and successful theories of modern physical science. It has been estimated that its principles form the basis for about 30 per cent of the world's manufacturing economy. This is all the more remarkable because quantum theory is a theory that nobody understands. The meaning of Quantum Theory introduces science students to the theory's fundamental conceptual and philosophical problems, and the basis of its non-understandability. It does this with the barest minimum of jargon and (...)
  34. Can One Detect the State of an Individual System?L. E. Ballentine - 1992 - Foundations of Physics 22 (3):333-342.
    Some interpretations of quantum mechanics regard a mixed quantum state as a ensemble, each individual member of which has a definite but unknown state vector. Other interpretations ascribe a state vector only to anensemble of similarly prepared systems, but not to anindividual. Previous attempts to detect the hypothetical individual state vectors have failed, essentially because the state operator enters the relevant equations linearly. An example from nonlinear dynamics, in which a density matrix enters nonlinearly, is examined because it might appear (...)
  35. Classicality Without Decoherence: A Reply to Schlosshauer. [REVIEW]Leslie Ballentine - 2008 - Foundations of Physics 38 (10):916-922.
    Schlosshauer has criticized the conclusion of Wiebe and Ballentine (Phys. Rev. A 72:022109, 2005) that decoherence is not essential for the emergence of classicality from quantum mechanics. I reply to the issues raised in his critique, which range from the interpretation of quantum mechanics to the criterion for classicality, and conclude that the role of decoherence in these issues is much more restricted than is often claimed.
  36. The Empirical Determination of Quantum States.William Band & James L. Park - 1970 - Foundations of Physics 1 (2):133-144.
    A common approach to quantum physics is enshrouded in a jargon which treats state vectors as attributes of physical systems and the concept of state preparation as a filtration scheme wherein a process involving measurement selects from a primordial assembly of systems those bearing some prescribed vector of interest. By contrast, the empirical experiences with which quantum theory is actually concerned relate measurement and preparation in quite an opposite manner. Reproducible preparation schemes are logically and temporally anterior to measurement acts. (...)
  37. Wigner's Friend and Bell's Field Beables.Jeffrey A. Barrett - unknown
    A field-theoretic version of Wigner’s friend (1961) illustrates how the quantum measurement problem arises for field theory. Similarly, considering spacelike separate measurements of entangled fields by observers akin to Wigner’s friend shows the sense in which relativistic constraints make the measurement problem particularly difficult to resolve in the context of a relativistic field theory. We will consider proposals by Wigner (1961), Bloch (1967), Helwig and Kraus (1970), and Bell (1984) for resolving the measurement problem for quantum field theory. We will (...)
  38. On the Nature of Measurement Records in Relativistic Quantum Field Theory.Jeffrey A. Barrett - unknown
    A resolution of the quantum measurement problem would require one to explain how it is that we end up with determinate records at the end of our measurements. Metaphysical commitments typically do real work in such an explanation. Indeed, one should not be satisfied with one's metaphysical commitments unless one can provide some account of determinate measurement records. I will explain some of the problems in getting determinate records in relativistic quantum field theory and pay particular attention to the relationship (...)
  39. On Testing for the Stage of Collapse in Quantum Mechanics.Lon Stephen Becker - 1998 - Dissertation, University of Illinois at Chicago
    The question was considered whether it is possible to experimentally narrow down the time of collapse in the measurement process of quantum mechanics. A form of experiment was developed towards that end. ;The proof of John von Neumann that it is impossible to determine the time of collapse was analyzed, and its hidden assumptions were exploited in the design of the experiment. The reinterpretation of quantum mechanics by David Bohm was introduced to give an alternative way of looking at quantum (...)
  40. Nondemolition Principle of Quantum Measurement Theory.V. P. Belavkin - 1994 - Foundations of Physics 24 (5):685-714.
    We give an explicit axiomatic formulation of the quantum measurement theory which is free of the projection postulate. It is based on the generalized nondemolition principle applicable also to the unsharp, continuous-spectrum and continuous-in-time observations. The “collapsed state-vector” after the “objectification” is simply treated as a random vector of the a posterioristate given by the quantum filtering, i.e., the conditioning of the a prioriinduced state on the corresponding reduced algebra. The nonlinear phenomenological equation of “continuous spontaneous localization” has been derived (...)
  41. Against ”Measurement'.J. S. Bell - 2004 - In Speakable and Unspeakable in Quantum Mechanics. Cambridge University Press. pp. 213--231.
  42. Speakable and Unspeakable in Quantum Mechanics: Collected Papers on Quantum Philosophy.J. S. Bell - 2004 - Cambridge University Press.
    This book comprises all of John Bell's published and unpublished papers in the field of quantum mechanics, including two papers that appeared after the first edition was published. It also contains a preface written for the first edition, and an introduction by Alain Aspect that puts into context Bell's great contribution to the quantum philosophy debate. One of the leading expositors and interpreters of modern quantum theory, John Bell played a major role in the development of our current understanding of (...)
  43. Six Possible Worlds of Quantum Mechanics.J. S. Bell - 1992 - Foundations of Physics 22 (10):1201-1215.
  44. 6 Possible Worlds of Quantum-Mechanics (Reprinted From Possible Worlds in Humanities Arts and Sciences, Pg 359-373, 1989). [REVIEW]Js Bell - 1992 - Foundations of Physics 22 (10):1201-1215.
  45. The Conceptual and the Anecdotal History of Quantum Mechanics.Mara Beller - 1996 - Foundations of Physics 26 (4):545-557.
    The aim of this paper is to combine the intellectual and the psychosocial aspects. blurring the distinction between the conceptual and the anecdotal history of quantum mechanics. The full realization of the importance of such “anecdotal” factors leads to the revision of our understanding of the conceptual development itself. The paper concludes with the suggestion that a major part of numerous inconsistencies in the Copenhagen interpretation of quantum physics are of a psychosocial origin.
  46. Book Reviews. [REVIEW]Gordon Belot - 1997 - International Studies in the Philosophy of Science 11 (3):305-313.
  47. Quantum Theory and the Flight From Realism - Christopher Norris, Routledge, London, New York, IX +266pp., $26.00 Paperback, ISBN 0-415-22322-. [REVIEW]Y. Ben-Menahem - 2002 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 33 (3):587-591.
  48. Dummett Vs Bell on Quantum Mechanics.Yemima Ben-Menahem - 1997 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 28 (2):277-290.
  49. On Procedures for the Measurement of Questions in Quantum Mechanics.Paul Benioff - 1975 - Foundations of Physics 5 (2):251-255.
    It is shown that there exist observablesA and Borel setsE such that the procedure “measureA and give as output the number 1 (0) if theA measurement outcome is (is not) inE” does not correspond to a measurement of the proposition observable ℰA(E) usually assigned to such procedures. This result is discussed in terms of limitations on choice powers of observers.
  50. On Definitions of Validity Applied to Quantum Theories.Paul Benioff - 1973 - Foundations of Physics 3 (3):359-379.
    In this work, quantum theories are considered which consist in essence of a map from state preparation proceduresw to states and a map from decision proceduresQ to probability operator measures. Two definitions of validity, similar to that given elsewhere, are given and compared for these theories. One definition is given in terms of one carrying out of somew followed by someQ, denoted by(Q, w). The other is given in terms of infinite repetitions(Q, w) ofw followed byQ. Both definitions are discussed (...)
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