Dissipating the quantum measurement problem

2009

According to our modal-Hamiltonian interpretation (MHI) of quantum mechanics, the Hamiltonian of the closed system defines the set of its definite-valued observables. This definition seems to be incompatible with the pointer basis selected by the environment-induced decoherence (EID) of the open system. In this paper we argue that decoherence can be understood from a closed system perspective which (i) shows that the incompatibility between MHI and EID is only apparent, and (ii) solves certain conceptual challenges that the EID program still has to face.

New Journal of Physics

Physical Review A, 1994

The modal interpretation explained here construes the mathematical formalism of quantum mechanics in terms of physical properties (" be-ables, " "existents") in such a way that the property attribution rejects the mathematical structure as much as possibleno additional structure is superimposed on the formalism. We generalize the interpretation by specifying a dynamics of physical properties, and also extend it while replying to recent objections by Albert and Loewer [Proceedings of the 1990 Biennial Meeting of the Philosophy of Science Association, edited by A. Fine, M.

Physics Letters A, 1989

In the recent literature therehave been several proposalsto solve the quantum mechanical measurement problem by taking into account that in measurement interactions there are many unobserved degrees of freedom. Tracing out the unobserved degrees of freedom results in decoherence between components ofthe wave function. This effectively implies transition to a mixture, which is then taken to explain the "reduction ofthe wave packet". It is here pointed out that such "solutions" are unsatisfactory as they stand, and must be supplemented by a new empirical interpretation ofthe formal state description ofquantum mechanics.

Poznan Studies in the Philosophy of the Sciences and the Humanities, 2006

In the article the possibility of breaking the eigenvalue-eigenstate link in quantum mechanics is considered. An argument is presented to the effect that there are some non-maximal observables for which the implication from eigenstates to eigenvalues is not valid, i.e. such that although the probability of revealing certain value upon measurement is one, they don't possess this value before the measurement. It is shown that the existence of such observables leads to contextuality, i.e. the thesis that one Hermitean operator can represent more than one physical observable. Finally, contextuality brought about by these considerations is compared with contextuality suggested by the Kochen-Specker paradox.

2022

The Quantum Measurement Problem is arguably one of the most debated issues in the philosophy of Quantum Mechanics, since it represents not only a technical difficulty for the standard formulation of the theory, but also a source of interpretational disputes concerning the meaning of the quantum postulates. Another conundrum intimately connected with the QMP is the Wigner friend paradox, a thought experiment underlining the incoherence between the two dynamical laws governing the behavior of quantum systems, i.e the Schrödinger equation and the projection rule. Thus, every alternative interpretation aiming to be considered a sound formulation of QM must provide an explanation to these puzzles associated with quantum measurements. It is the aim of the present essay to discuss them in the context of Relational Quantum Mechanics. In fact, it is shown here how this interpretative framework dissolves the QMP. More precisely, two variants of this issue are considered: on the one hand, I focus on the "the problem of outcomes" contained in Maudlin (1995) - in which the projection postulate is not mentioned - on the other hand, I take into account Rovelli's reformulation of this problem proposed in Rovelli (2022), where the tension between the Schrödinger equation and the stochastic nature of the collapse rule is explicitly considered. Moreover, the relational explanation to the Wigner's friend paradox is reviewed, taking also into account some interesting objections contra Rovelli's theory contained in Laudisa (2019). I contend that answering these critical remarks leads to an improvement of our understanding of RQM. Finally, a possible objection against the relational solution to the QMP is presented and addressed.

Quantum Reality, Relativistic Causality, and Closing the Epistemic Circle (eds. W.C. Myrvold, J. Christian), pp. 229-256, 2009

In this contribution I review rigorous formulations of a variety of limitations of measurability in quantum mechanics. To this end I begin with a brief presentation of the conceptual tools of modern measurement theory. I will make precise the notion that quantum measurements necessarily alter the system under investigation and elucidate its connection with the complementarity and uncertainty principles.

Filozofia Nauki, 2014

The dispositional account of quantum properties faces the following circularity problem: properties of a system are defined as dispositions (probabilistic or deterministic) to give rise to certain outcomes upon measurements, but measurements in turn are generally characterized with reference to the very same dispositions. I consider one way of escaping the difficulty with regard to probabilistic dispositions by applying a theorem due to Peter Mittelstaedt. The theorem enables us to give a probability-free characterization of quantum measurements, thus eliminating the need of referring back to probabilistic dispositions of the system. However, the circularity problem remains for deterministic dispositions. I give arguments why we should resist the temptation to interpret eigenstates as categorical properties, and I discuss possible alternative solutions to the problem.

2019

Measurement in science is central and flawed. The major difference between Classical Mechanics (CM) and Quantum Mechanics (QM) lie in the assumptions of measurement. In CM, all measurements were assumed to be 'harmless' and repeatable being an immediate interpretation of the algebraic variables. In QM, it has been recognized that ALL observations affect the target system but repetition of the exactly identical initial conditions are possible. There is an explicit formula used for linking the Wave-Function of 'observable' variables to arithmetic numbers uncovered in exactly repeatable experiments leading to a frequency-probabilistic interpretation of the arithmetic numbers. These assumptions are critically analyzed based on a misunderstanding of the role of measurement. The report is major part of a research programme (UET) based on a new theory of the electromagnetism (EM), centered exclusively on the interaction between electrons. All the previous papers to date in this series have presented a realistic view of the dynamics of two or more electrons as they interact only between themselves. This paper now posits a theory of how this microscopic activity is perceived by human beings in attempting to extract information about atomic systems. The standard theory of quantum mechanics is constructed on only how the micro-world appears to macro measurements-as such, it cannot offer any view of how the foundations of the world are acting when humans are NOT observing it (the vast majority of the time)-This has generated almost 100 years of confusion and contradiction at the very heart of physics. We now know that all human beings (and all our instruments) are vast collections of electrons, our information about atomic-scale can only be obtained destructively and statistically. This theory now extends the realistic model of digital electrons by adding an explicit measurement model of how our macro instruments interfere with nature's micro-systems when such attempts result in human-scale information. The focus here is on the connection between the micro-world (when left to itself) and our mental models of this sphere of material reality, via the mechanism of atomic measurements. The mathematics of quantum mechanics reflects the eigenvalues of the combined target system PLUS equipment used for measurement together. Therefore, QM has constructed a theory that inseparably conflates the ontological and epistemological views of nature. This standard approach fails to examine isolated target systems alone. It is metaphysically deficient. This critical investigation concludes that the Quantum State function (Ψ) is not a representation of physical reality, within a single atom, but a generator function for producing the average statistical results on many atoms of this type. In contrast, the present theory builds on the physical reality of micro-states of single atoms, where (in the case of hydrogen), a single electron executes a series of fixed segments (corresponding to the micro-states) across the atom between a finite number of discrete interactions between the electron and one of the positrons in the nucleus. The set of temporal segments form closed trajectories with real temporal periods, contra to Heisenberg's 'papal' decree banning such reality because of his need to measure position and momentum at all times; even though instantaneous momentum is never measured.