Presenting a realistic interpretation of quantum mechanics and, in particular, a realistic view of quantum waves, this book defends, with one exception, Schrodinger's views on quantum mechanics. Johansson goes on to defend the view that the collapse of a wave function during a measurement is a real physical collapse of a wave and argues that the collapse is a consequence of quantisation of interaction. Lastly Johansson argues for a revised principle of individuation in the quantum domain and that this principle enables a sort of explanation of non-local phenomena.
Presenting a realistic interpretation of quantum mechanics and, in particular, a realistic view of quantum waves, this book defends, with one exception, Schrodinger's views on quantum mechanics. Johansson goes on to defend the view that the collapse of a wave function during a measurement is a real physical collapse of a wave and argues that the collapse is a consequence of quantisation of interaction. Lastly Johansson argues for a revised principle of individuation in the quantum domain and that this principle enables a sort of explanation of non-local phenomena.
The present paper contains a new attack on the measurement problem. The point of departure is a realist view according to which i) state functions in quantum theory describe physical states of affairs and not information states attributed to observers, and ii) in theses states, some observables are indeterminate and not merely unknown, i.e., value determinism is rejected. Furthermore, quantisation of interaction is accepted as an empirically established fact, independently of any interpretations of quantum theory. From these assumptions it follows that Hermitian operators replacing classical variables may be viewed as representing actions from the environment done on physical systems represented by the state functions upon which the operators operate. Sometimes this influence is followed by a discontinuous, indeterministic and irreversible state change; in other words, the system undergoes a collapse, which is represented by a projection operator. Thus, assuming a realistic view on quantum states and their changes, we have an explanation for the collapse of the wave function. Since the collapse is a discontinuous, random and irreversible state change, the classical form of physical explanation in terms of a mechanism which describes how a system continuously changes its state is impossible. Hence, if we accept quantisation of interaction, we must give up our demand for a ordinary mechanical explanation for the collapse. Neither can we state, in advance, sufficient conditions for the collapse, since it is an indeterministic theory.
In the interpretation of Quantum Mechanics, there were four major mistakes done at different levels: (1)A misinterpretation of Bell’s theorem in which the original intent did not include non-locality, but as a test to see whether or not a particle has a certain property that can be measured. (2)A misinterpretation of the disagreement between Einstein and Bohr. Einstein’s objection to the collapse of the wave function implied a spooky action at a distance, while Bohr insisted on the instantaneous collapse of the wave function which he mistook to be a real wave. (3)A misinterpretation that the wave function represents a real wave when in actuality it represents the possible states of a quantum system before a measurement. (4)When Bell’s theorem was violated by a quantum system, those violations were misinterpreted as evidence of an instantaneous collapse of the wave function and non-locality. We will argue: there is no collapse of the wave function. Bell’s theorem is not about non-locality. There is no spooky action at a distance. And Quantum Mechanics is about measuring quantities at the microscopic scales and in doing so, these quantities are altered. So what we get is partial knowledge. But in spite of that obstacle, we still get a theory of reality with considerable success.
In the well known Copenhagen interpretation of Quantum mechanics, advocated by N. Bohr, the physical objects and the experimental results can be described only in a macroscopic language, leaving any possible microscopic description as unspeakable. This point of view has been deepened by C. Rovelli in the relational interpretation of Quantum mechanics. Most of the alternative interpretations, which try a detailed microscopic description of physical phenomena and of their evolution, have in common the explicit introduction of the wave function as the basic element of the theory. These interpretations require the notion of quantum state as the fundamental concept of the theory, which is the typical unspeakable physical element according to the Copenhagen interpretation. The two basic physical entities are intimately bound together by the integrity of the wave function. These interpretations are usually indicated as realistic. It is well known that the use of the wave function and its time evolution in the description of the physical processes leads unavoidably to some difficulties or so-called paradoxes. The measurement problem is at the center of these difficulties, mainly because it requires the introduction of the reduction process of the wave function, which is not included explicitly within the mathematical formalism of Quantum Mechanics. In this paper we build up and propose a model which goes beyond the standard formalism and which is able to solve the measurement problem and all the other difficulties which, in a way or in another, are related to it.
Although quantum mechanics is generally considered to be fundamentally incompatible with classical logic, it is argued here that the gap is not as great as it seems. Any classical, discrete, time reversible system can be naturally described using a quantum Hubert space, operators, and a Schrödinger equation. The quantum states generated this way resemble the ones in the real world so much that one wonders why this could not be used to interpret all of quantum mechanics this way. Indeed, such an interpretation leads to the most natural explanation as to why a wave function appears to "collapse" when a measurement is made, and why probabilities obey the Born rule. Because it is real quantum mechanics that we generate, Bell's inequalities should not be an obstacle.
The Quantum Mechanics is interpreted, in this article, in a simple and direct way. By combining the unitary evolution with the quantum condition that observations require the state vector to be an eigenstate of the observable, a discontinuity in evolution (the state vector reduction) seems to be mandatory. Thus, for each such discontinuity, new initial conditions for the time evolution state vector are needed, and they are obtained by measurements. Delayed-choice experiments suggest that these new initial conditions are specified after the discontinuity takes place. Consequently, because it needs initial conditions that can be specified with a delay, the time evolving state vector is semi-realistic (in the sense that it is not completely specified until the measurement is performed), and not entirely realistic. The collapse of the wave function, especially when it is combined with the entanglement, seems to be a non-local phenomenon. In fact, the non-locality is present only as a consistency requirement for the initial conditions needed to select a solution of the evolution equation. The Direct Interpretation is intended to provide to our intuition a physical background, for helping us thinking about quantum phenomena. It identifies the main counterintuitive parts of the Quantum Mechanics in the discontinuity and the delayed initial conditions. Because it makes minimal assumptions, it is compatible with the main interpretations of Quantum Mechanics. Two principal unclear points of Quantum Mechanics are identified in the discontinuities, and the measurement problem. Both problems will be approached in subsequent articles.
Abstract It has been shown that quantum mechanics in its orthodox interpretation violates four different formulations of causality principle endowed with empirical meaning. The present work aims to highlight how even a realistic non-standard interpretation of the theory conflicts with causality in its Cartesian formulation of the principle of the non-inferiority of causes over effects. Such an interpretation, which attributes some form of weak physical reality to the wave function (called empty wave, regarded as a zero-energy wave-like phenomenon), is a sort of precursor of the more recent so-called wavefunction realism. We also discuss a more radical realistic interpretation according to which physical properties can also be assigned to non-metaphysical relative nothing, seen as the simple absence of a particle such as a photon, but not of its corresponding state (no-photon), which is considered real. By interpreting the wave function collapse as a consequence of an interaction with empty waves or of a detection of the no-photon, we will highlight how more real physical effects can derive from lower causes, including relative nothing. Finally, we will show how these interpretations, while violating Cartesian causality in its two variants, do not seem to affect the validity of the principle of a rational explanation that nothing can derive from (absolute) nothing, which does not seem satisfied by the orthodox interpretation.