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The Bare Theory and Determinate Experience

Jeffrey Alan Barrett

Published Aug 16, 2001• 0 citations
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Abstract

Abstract This chapter begins by discussing several strategies for interpreting the global state. Next, it explains that the bare theory is simply the standard von Neumann–Dirac formulation of quantum mechanics with the standard interpretation of states (the eigenvalue-eigenstate link) without the collapse postulate — hence, bare. Subsequently, it examines several suggestive properties of the bare theory that tell what an observer would report concerning his experience in various measurement situations if the theory were true. It then explains that all measurement interactions induce an imperfect correlation between the state of an observer's most immediately accessible physical records and the observed quantity of the object system without disturbing the property being measured. This chapter also differentiates ordinary and disjunctive records, experiences, and beliefs. Lastly, it discusses several problems encountered with the bare theory.

DOI
10.1093/acprof:oso/9780199247431.003.0004

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Abstract This chapter begins by discussing several strategies for interpreting the global state. Next, it explains that the bare theory is simply the standard von Neumann–Dirac formulation of quantum mechanics with the standard interpretation of states (the eigenvalue-eigenstate link) without the collapse postulate — hence, bare. Subsequently, it examines several suggestive properties of the bare theory that tell what an observer would report concerning his experience in various measurement situations if the theory were true. It then explains that all measurement interactions induce an imperfect correlation between the state of an observer's most immediately accessible physical records and the observed quantity of the object system without disturbing the property being measured. This chapter also differentiates ordinary and disjunctive records, experiences, and beliefs. Lastly, it discusses several problems encountered with the bare theory.
Abstract The book starts with a description of classical mechanics then discusses the quantum phenomena that require us to give up our commonsense classical intuitions. We consider the physical and conceptual arguments that led to the standard von Neumann-Dirac formulation of quantum mechanics and how the standard theory explains quantum phenomena. This includes a discussion of how the theory’s two dynamical laws work with the standard interpretation of states to explain determinate measurement records, quantum statistics, interference effects, entanglement, decoherence, and quantum nonlocality. A careful understanding of how the standard theory works ultimately leads to the quantum measurement problem. We consider how the measurement problem threatens the logical consistency of the standard theory then turn to a discussion of the main proposals for resolving it. This includes collapse formulations of quantum mechanics like Wigner’s extension of the standard theory and the GRW approach and no-collapse formulations like pure wave mechanics, the various many-worlds theories, and Bohmian mechanics. In discussing alternative formulations of quantum mechanics we pay particular attention to the explanatory role played by each theory’s empirical ontology and associated metaphysical commitments and the conceptual trade-offs between theoretical options.
Abstract The standard von Neumann-Dirac formulation of quantum mechanics is presented as a set of five basic rules. We discuss each rule is discussed in turn paying particular attention to the conceptual history of the theory. Of central importance is the standard interpretation of states (the eigenvalue-eigenstate link) and the dynamical laws of the theory (the random collapse dynamics and the deterministic linear dynamics) and how the interpretation and dynamics work together to predict and explain the results of basic quantum experiments. While the focus is on the behavior of electrons, we also briefly consider how the theory uses the same mathematical formalism to treat other phenomena like the behavior of neutral K mesons and qbits in a quantum computer.
Abstract This chapter begins by discussing the problems encountered in interpreting Everett's assumption of the same appearances in pure wave mechanics as predicted by the standard collapse theory. The significant gaps at critical points in his exposition and the contradicting evidence of what he wanted, explain the many mutually incompatible reconstructions of Everett that apologists and critics have devised. This chapter also provides the author's interpretation of the various theories discussed in this book.
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This article surveys a selection of key conceptual and interpretational developments in quantum mechanics, tracing the theory from its foundational postulates to contemporary discussions of measurement, nonlocality, and the emergence of classicality. Beginning with the structure of Hilbert space and the postulates governing state evolution and measurement, the epistemic stance of the Copenhagen interpretation and its modern reformulations are examined. The Einstein-Podolsky-Rosen argument, Bell's theorem, and Hardy's paradox are then discussed as probes of locality and realism, alongside the deterministic but explicitly nonlocal de Broglie-Bohm theory. The measurement problem and the implications of contextuality are analyzed in relation to objective collapse models, which introduce new physical dynamics to account for definite outcomes. Finally, the role of decoherence in the suppression of interference and the emergence of classical behavior is explored, together with the interpretational frameworks of many-worlds and consistent histories. This material aims to provide a coherent introductory overview of how several of the most prominent interpretations address the central concern of what quantum mechanics tells us about the nature of physical reality.