The development of the subjective solutions to the problem of measurement in quantum mechanics is presented. It is shown that - already in 1932 - von Neumann faced a dilemma: either quantum mechanics represents the only true physical reality and then the reduction of the wave packet is illusory, or the mind is able to act on the physical world producing a transition that is not allowed by quantum- mechanical laws. We show that the first alternative was followed by the many-world or many-mind interpretation, the second by the school of London-Bauer and Wigner. The difficulties of these two interpretations are also pointed out. Finally a third possibility, proposed by Albert and Loewer, is presented: The evolution of mind is independent from that of the physical world and is subjected to its own laws.
The development of the subjective solutions to the problem of measurement in quantum mechanics is presented. It is shown that - already in 1932 - von Neumann faced a dilemma: either quantum mechanics represents the only true physical reality and then the reduction of the wave packet is illusory, or the mind is able to act on the physical world producing a transition that is not allowed by quantum- mechanical laws. We show that the first alternative was followed by the many-world or many-mind interpretation, the second by the school of London-Bauer and Wigner. The difficulties of these two interpretations are also pointed out. Finally a third possibility, proposed by Albert and Loewer, is presented: The evolution of mind is independent from that of the physical world and is subjected to its own laws.
Dualistic interpretations attempt to solve the measurement problem of quantum mechanics by postulating the existence of non-physical minds, and by giving a suitable dynamical equation for how these minds evolve. I consider the relative merits of three extant dualistic interpretations (Albert and Loewer’s single-mind and many-minds interpretations, and Squires’ interpretation), and I defend Squires’ interpretation as preferable to the Albert/Loewer interpretations. I also argue that, for all three of these interpretations, the minds evolve independently of the physical universe, and hence render the physical universe otiose; the interpretations are better viewed as supporting not dualism, but mental monism.
This work presents a historical-epistemological analysis of the foundations of quantum mechanics. From a philosophical point of view, the relationships between quantum mechanics and scientific realism are highlighted, as well as the influence of the neo-positivist philosophy of the first decades of the 20th century. The great significance of measurement in the context of quantum mechanics is underlined, as an essential element in providing a coherent description of reality moving from the microcosm to the macrocosm, as well as the role that the measurement apparatus and the consciousness of the observer assume during the act of measurement, the ontological problem, the problem of the objectification of the wave function and the problem of the definition of discernibility. This is followed by an overview of the most important alternative proposals to the standard interpretation (Copenhagen interpretation), with particular reference to hidden variable theories, and other alternatives to standard quantum mechanics that profoundly modify the vision of reality, such as the Everett’s many-worlds theory, the QBism, the unified holistic approach.
The problem of quantum measurement is an important epistemological problem in philosophical researches of quantum mechanics.Aim at von Neumann's wave packet collapse hypothesis and Bohr's quantum-classical dichotomy,physicists had put forward some alternative solutions that are different from the standard interpretation since 1950s.As historical outcomes in endless flow of development of scientific theory,these alternative solutions indicate that the development of scientific theory always tends to aspects of consistency,apprehensible and testability.
Abstract After the excellent agreement between the theory and experimental observations was established, many workers, partly in response to EPR, returned to consider the physical meaning of the theory. Several workers, e.g., London and Bauer, Wigner, and von Neumann, believed conscious observers played a key role. The failure to observe superposition states at the macroscopic level meant that superpositions had to be destroyed (collapse) at some level. This was called the Heisenberg or von Neumann cut and played a role in the interpretation. In more modern times David Bohm resuscitated de Broglie’s pilot wave theory and Hugh Everett proposed the “many worlds interpretation.” Other modern interpretation attempts include the theory of decoherence, promoted by Zurek, and spontaneous collapse theories. These discussions should be conducted in the framework of second quantization, the most refined form of the theory, which provides a solution to the 3N dimensional problem and insights into wave-particle duality.
In recent decades, progress in the field of neurosciences has triggered an interest in understanding mind-brain relationships. Quantum Mechanics (QM) has been present in the debate from its beginnings through the well-known measurement paradox. The standard interpretation of QM considers two basic, fundamentally irreducible, processes: the deterministic evolution of the wave-function according to the Schrodinger equation, once the initial conditions have been settled; and the indeterministic wave-function collapse into one of the possible outcomes, after performing a specific measurement. So, QM would point to the limits of a purely deterministic view of nature and, in particular, of brains. Nevertheless, QM’s relevance for the brain’s physics is still to be proven. Detractors of the QM influence are confident of the role of decoherent processes at different physical scales in order to ensure a classical deterministic behavior of the brain. However, little attention is paid to the epistemic implications of invoking decoherence for the mind-brain problem. In this paper, (i) we present lasting QM models stating a specific view of human consciousness and make explicit their position regarding the relationship between the physical activity of neurons and/or networks of neurons and the phenomenal conscious experience; (ii) we review the main criticisms of the relevance of QM in the brain and, most importantly, we bring out the philosophical implications behind the usual recourse to decoherence in the transition from the quantum to the classical world, explaining why the mind-brain problem and the measurement paradox should not be disentangled.
A minimal approach to the measurement problem and the quantum-to-classical transition assumes a universally valid quantum formalism, i.e. unitary time evolution governed by a Schrödinger-type equation. As had been pointed out long ago, in this view the measurement process can be described by decoherence which results in a "Many-Worlds" or "Many-Minds" scenario according to Everett and Zeh. A silent assumption for decoherence to proceed is however, that there exists incomplete information about the environment our object system gets entangled with in the measurement process. This paper addresses the question where this information is traced out and - by adopting recent approaches to model consciousness in neuroscience - argues that a rigorous interpretation results in a modern perspective on the von-Neumann-Wigner interpretation - namely that the information that is or is not available in the consciousness of the observer is crucial for the definition of the environment. As such the quantum-to-classical transition while being difficult or impossible to probe in physics may become testable in psychology.