Quantum mechanics has sometimes been taken to be an empiricist (vs. realist) theory. I state the empiricist's argument, then outline a recently noticed type of measurement--protective measurement--that affords a good reply for the realist. This paper is a reply to scientific empiricism (about quantum mechanics), but is neither a refutation of that position, nor an argument in favor of scientific realism. Rather, my aim is to place realism and empiricism on an even score in regards to quantum theory.

I show that frequentism, as an explanation of probability in classical statistical mechanics, can be extended in a natural way to a decoherent quantum history space, the analogue of a classical phase space. The result is a form of finite frequentism, in which Gibbs’ concept of an infinite ensemble of gases is replaced by the quantum state expressed as a superposition of a finite number of decohering microstates. It is a form of finite and actual frequentism (as opposed to hypothetical (...) frequentism) insofar as all the microstates exist, in keeping with the decoherence-based Everett interpretation, and some versions of pilot-wave theory. (shrink)

We question the free energy principle (FEP) as it is used in contemporary physics. If the FEP is incorrect in physics, then it cannot ground the authors' arguments. We also question the assumption that perception requires inference. We argue that perception (including perception of social affordances) can be direct, in which case inference is not required.

Early in 1926 Erwin Schrodinger presented his famous theory of wave mechanics to account for atomic phenomena. It is often assumed that Schrodinger’s work reflected a realist philosophy. In this article, I will argue that this assumption is incorrect.

This paper deals with the development of, and the current discussion about, the interpretation of quantum mechanics. The following topics are discussed: 1. The Copenhagen Interpretation, 2. Formal Problems of Quantum Mechanics, 3. Process of Measurement and the Equation of Motion, 4. Macroscopic Level of Description, 5. Search for Hidden Variables, 6. The Notion of “Reality” and Epistemology of Quantum Mechanics, 7. Quantum Mechanics and the Explanation of Life.The Bohr‐Einstein dialogue on the validity of the quantum mechanical description of physical (...) reality lasted over two decades. Since the early nineteen fifties, Wiper has provided much of the point and counterpoint of the continuing discussion on the interpretation and epistemology of quantum mechanics. We have explored Wiper's views in some detail against the background of historical development and current debate. (shrink)

Quantum theory determines the evolution of quantum states between quantum jumps. Quantum theory also allows us to calculate rates of quantum jumps and, on a probabilistic level, the outcomes of those quantum jumps. Both quantum jumps and the continuous evolution of quantum states are important in the time evolution of quantum systems, and the scattering matrix ties those seemingly disparate concepts together. Indeed, quantum jumps are so essential in quantum dynamics that we should refocus discussion of a quantum ontology on (...) the power and principal limitations of our knowledge about quantum jumps as encoded in the scattering matrix. On the one hand, one might argue that the lack of a dynamical resolution of quantum jumps indicates an inherent incompleteness of the theory. However, we would rather submit that quantum theory is complete and that the observations indicate a principal limitation to the description of the universe as a smoothly evolving dynamical system. The modern understanding of quantum jumps therefore calls for updates to the Copenhagen interpretation instead of modifications of quantum theory. (shrink)

We present a Gedankenexperiment that leads to a violation of detailed balance if quantum mechanical transition probabilities are treated in the usual way by applying Fermi’s “golden rule”. This Gedankenexperiment introduces a collection of two-level systems that absorb and emit radiation randomly through non-reciprocal coupling to a waveguide, as realized in specific chiral quantum optical systems. The non-reciprocal coupling is modeled by a hermitean Hamiltonian and is compatible with the time-reversal invariance of unitary quantum dynamics. Surprisingly, the combination of non-reciprocity (...) with probabilistic radiation processes entails negative entropy production. Although the considered system appears to fulfill all conditions for Markovian stochastic dynamics, such a dynamics violates the Clausius inequality, a formulation of the second law of thermodynamics. Several implications concerning the interpretation of the quantum mechanical formalism are discussed. (shrink)

“What did the President know and when did he know it?”Senator Howard Baker, Watergate hearings, 1973Why do scientists accept or reject theories? More specifically: why do they change from one theory to another? What is the role of empirical tests in the evaluation of theories?This paper focuses on a narrowly-defined question: in judging theories, do scientists give greater weight (other things being equal) to successfulnovel predictionsthan to successful deductions of previously-known facts? The affirmative answer is called the “predictivist thesis” (Maher (...) 1988).It is primarily philosophers who are interested in this question, and they have treated it mostly as a normative or logical problem. Can the writings of historians of science tell us how scientists have treated novel predictions in the past? Until recently historians have rarely addressed this point. (shrink)

I introduce and review the most recent and most promising model of state vector reduction, that of Ghirardi, Rimini, Weber, and Pearle. This model requires the specification of a reduction basis. At least two questions therefore arise: Are there physical reasons to choose one basis rather than another? Does the choice made lead to any undesirable consequences? I argue that there arephysical reasons to choose from a certain class of reduction bases (a class which includes the choice made by the (...) authors mentioned above), and that such a choice does not lead to problems, contra an argument by Albert and Vaidman. (shrink)

On the occasion of the centennial of his birth, Schrödinger's life and views are sketched and his critique of the interpretation of quantum mechanics accepted at his time is examined. His own interpretation, which he had to abandon after a short time, provides a prime example of the way in which the tentative meaning of central theoretical terms in a new and revolutionary theory often fails. Schrödinger's strong philosophical convictions have played a key role in his refusal to break with (...) many of the notions of classical physics. At the same time, they made him into a keen and incisive critic of the Copenhagen interpretation. His criticism is compared with present views on quantum mechanics. (shrink)

This paper argues against the possibility of presenting a consistent version of the Copenhagen Interpretation of Quantum Physics, characterizing its founders' philosophical pronouncements including those on the realism-antirealism issue, as a contingent collection of local, often contradictory, moves in changing theoretical and sociopolitical circumstances. The paper analyzes the fundamental differences of opinion between Bohr and the mathematical physicists, Heisenberg and Born, concerning the foundational doctrine of the "indispensability of classical concepts", and their related disagreements on "quantum reality." The paper concludes (...) with an explanation of how the appearance of consensus was achieved despite fundamental disagreements among the proponents. The paper undermines the adequacy of the notion of a general conceptual framework to describe the philosophical endeavors of working scientists. (shrink)

The apparent dichotomy between quantum jumps on the one hand, and continuous time evolution according to wave equations on the other hand, provided a challenge to Bohr’s proposal of quantum jumps in atoms. Furthermore, Schrödinger’s time-dependent equation also seemed to require a modification of the explanation for the origin of line spectra due to the apparent possibility of superpositions of energy eigenstates for different energy levels. Indeed, Schrödinger himself proposed a quantum beat mechanism for the generation of discrete line spectra (...) from superpositions of eigenstates with different energies. However, these issues between old quantum theory and Schrödinger’s wave mechanics were correctly resolved only after the development and full implementation of photon quantization. The second quantized scattering matrix formalism reconciles quantum jumps with continuous time evolution through the identification of quantum jumps with transitions between different sectors of Fock space. The continuous evolution of quantum states is then recognized as a sum over continually evolving jump amplitudes between different sectors in Fock space. In today’s terminology, this suggests that linear combinations of scattering matrix elements are epistemic sums over ontic states. Insights from the resolution of the dichotomy between quantum jumps and continuous time evolution therefore hold important lessons for modern research both on interpretations of quantum mechanics and on the foundations of quantum computing. They demonstrate that discussions of interpretations of quantum theory necessarily need to take into account field quantization. They also demonstrate the limitations of the role of wave equations in quantum theory, and caution us that superpositions of quantum states for the formation of qubits may be more limited than usually expected. (shrink)

This article discusses the historical similarities and differences between Schroedinger's and de Broglie's ideas on wave mechanics and gives a biographical account of their scientific relationship. Their arguments over questions such as quantum jumps, the viability of particles within wave mechanics theory, and the inclusion of space, time, and relativity in quantum mechanics are analyzed. The final section of the paper considers the overall role of Schroedinger's ideas in modern quantum mechanics.

It is argued that the conventional formulation of quantum mechanics is inadequate: the usual interpretation of the mathematical formalism in terms of the results of measurements cannot be applied to situations in which discontinuous transitions (''quantum jumps'') are observed as they happen, since nothing that can be called a measurement happens at the moment of observation. Attempts to force such observations into the standard mould lead to absurd results: ''a watched pot never boils''. Experiments show both that this result is (...) correct when the experiment does indeed consist of a series of measurements, and that it is not when the experiment consists of a period of observation: quantum jumps do happen. The possibilities for improving the formulation by incorporating transitions in the basic postulates are reviewed, and a satisfactory postulate is obtained by modifying a suggestion of Bell's. This requires a distinction between the external description of the whole of a physical system and internal descriptions which are themselves physical events in the system. It is shown that this gives correct results for simple unstable systems and for the quantum-jump experiments. (shrink)

One of the most striking features of the epistemological situation of Quantum Mechanics is the number of interpretations and the many schools of thought, with no consensus on the way to understand the theory. In this article, I introduce a distinction between orthodox interpretations and heterodox interpretations of Quantum Mechanics: the orthodox interpretations preserve all the quantum principles while the heterodox interpretations replace at least one of them. Then, I argue that we have strong empirical and epistemological reasons to prefer (...) orthodox interpretations to heterodox interpretations. The first argument is that all the experiments on the foundations of Quantum Mechanics give a high degree of corroboration to the quantum principles and, consequently, to the orthodox interpretations. The second argument is that the scientific progress needs a consensus: this consensus is impossible with the heterodox interpretations, while it is possible with the orthodox interpretations. Giving the preference to the orthodox interpretations is a reasonable position which could preserve both a consensus on quantum principles and a plurality of views on Quantum Mechanics. (shrink)

This paper deals with the development of, and the current discussion about, the interpretation of quantum mechanics. The following topics are discussed: 1. The Copenhagen Interpretation, 2. Formal Problems of Quantum Mechanics, 3. Process of Measurement and the Equation of Motion, 4. Macroscopic Level of Description, 5. Search for Hidden Variables, 6. The Notion of “Reality” and Epistemology of Quantum Mechanics, 7. Quantum Mechanics and the Explanation of Life.The Bohr‐Einstein dialogue on the validity of the quantum mechanical description of physical (...) reality lasted over two decades. Since the early nineteen fifties, Wiper has provided much of the point and counterpoint of the continuing discussion on the interpretation and epistemology of quantum mechanics. We have explored Wiper's views in some detail against the background of historical development and current debate. (shrink)

Current economic ontology development has failed to confront two important errors associated with historicism. Embracing the linearity of economic value being directly attributed to the labor applied to natural resources taken together with efficiency arguments used to justify monetary policy on both the microlevel (transaction) and macrolevel (global trade), we know these legacies of the scientific method applied to economic systems have left the G-20 paralyzed to deal with structural failings evidenced from banking to business to economic policy. An exploration (...) of the structural modalities that impair our current capacity for adaptation and alternative methods for accounting for value is the basis for this inquiry. Integral accounting is proposed as a more suitable method to transition from scarcity-based market models to abundance-based modes of sustainable engagement. (shrink)