Any interpretation, being a translation from one language (for example, micro-) to another language (for example, macro-), rests in the unproven possibility of the same conclusionbility or expressiveness in describing phenomena of different levels of ontology. In this sense, any interpretation is inherently speculative. There is the language of the theory - and we should communicate by it. In addition, there is a meta-language of philosophical generalizations.
Any interpretation, being a translation from one language (for example, micro-) to another language (for example, macro-), rests in the unproven possibility of the same conclusionbility or expressiveness in describing phenomena of different levels of ontology. In this sense, any interpretation is inherently speculative. There is the language of the theory - and we should communicate by it. In addition, there is a meta-language of philosophical generalizations.
According to the Everett interpretation of quantum mechanics, the apparent paradoxes of quantum theory require no change either in our philosophical attitude toward scientific theories or in the formalism of quantum mechanics itself. Rather, the unaltered theory can be understood as a literal description of physical reality. But the physical reality thus described is one of many noninteracting, approximately classical worlds. These worlds enter the theory not at the fundamental level—they are nowhere to be found in the basic formalism—but at a higher, emergent level; in this sense they are (ontologically speaking) on a par with the ontology of the special sciences.
Whereas the technological applications of quantum mechanics are extraordinarily abundant, its ontological implications are very controversial. Not only did several interpretations of the original quantum formalism develop throughout the last century, but modifications of the primitive formalism were also proposed, introducing new relevant theoretical elements, which gave rise to very different quantum ontologies. This article highlights that the diversity of quantum ontologies reveals the impossibility of establishing an exclusive inference from the empirical success of a theory and its ontological truth. Since scientific objectifications in general —and those of quantum mechanics in particular— have a limited cognitive scope, they don’t allow choosing a specific interpretation of the theory among the many possible ones, so that meta-scientific criteria are required.
Abstract What does realism about the quantum state imply? What follows when quantum theory is applied without restriction, if need be, to the whole universe? These are the questions which are debated in this book. All the chapters start from the point of realism, and based on the need, or the aspiration, for a theory that unites micro- and macroworlds, at least in principle. But the further claim argued by some is that if you allow the Schrödinger equation unrestricted application, supposing the quantum state to be something physically real, then this universe is one of countlessly many others, constantly branching in time, all of which are real. The result is the many worlds theory, also known as the Everett interpretation of quantum mechanics. The contrary claim sees this picture of many worlds as in no sense inherent in quantum mechanics, even when the latter is allowed unrestricted scope and even given that the quantum state itself is something physically real. For this picture of branching worlds fails to make physical sense, let alone common sense, even on its own terms. The status of these worlds, what they are made of, is never adequately explained. Ordinary ideas about time and identity over time become hopelessly compromised. The concept of probability itself is brought into question. This picture of many branching worlds is inchoate, it is a vision, an error. There are realist alternatives to many worlds, some even that preserve the Schrödinger equation unchanged. Twenty chapters, accompanied by commentaries and discussions, examine these claims and counterclaims in depth. They focus first on the question of ontology, the existence of worlds, second on the interpretation of probability, and third on alternatives or additions to many worlds. The introduction offers a helpful guide to the arguments for the Everett interpretation, particularly as they have been formulated in the last two decades.
Whereas the technological applications of quantum mechanics are extraordinarily abundant, its ontological implications are very controversial. Not only did several interpretations of the original quantum formalism develop throughout the last century, but modifications of the primitive formalism were also proposed, introducing new relevant theoretical elements, which gave rise to very different quantum ontologies. This article highlights that the diversity of quantum ontologies reveals the impossibility of establishing an exclusive inference from the empirical success of a theory and its ontological truth. Since scientific objectifications in general —and those of quantum mechanics in particular— have a limited cognitive scope, they don’t allow choosing a specific interpretation of the theory among the many possible ones, so that meta-scientific criteria are required.
Standard quantum theory is highly successful in all its applications, from photons and atoms, to semiconductors, superconductors, quarks, and so on. Yet the need to understand what the theory is really trying to tell us about the nature of the world beyond specific predictions forces us into the realm of philosophy, or, as some have dubbed it, quantum metaphysics: the study of the interpretation of quantum mechanics. There is a wide range of opinions regarding the philosophical foundations of quantum mechanics. This chapter focuses on two of the most prominent interpretations: the Copenhagen interpretation, and one alternative interpretation that has been gaining some support in recent years, the many-worlds interpretation (MWI), also known as the many universes interpretation. The central issues of contention are: firstly, that the measurement of some attribute of a quantum system generally involves the probabilistic collapse, or reduction, of the state vector where the probabilistic nature of the process is inherent—that is, not reducible to a more fundamental, deterministic explanation; and, secondly, the problem of bringing a measurement to a completion—a problem generally known as the measurement paradox.