Physical Theory and its Interpretation

Enós E. Witmer

This paper deals with the problem of the interpretation of quantum mechanics, the nature of physical theory, and the future of physics. First, the question of why there are so many different interpretations of quantum mechanics proposed and accepted by outstanding quantum experts is treated. This requires a discussion of the relation between physics and philosophy and drawing a distinction between a physical formalism and a physical explanation. The Copenhagen interpretation is considered, criticized, and found to be unsatisfactory in some respects. Finally, an interpretation that contains ideas from previous interpretations but which may itself be new, is proposed. Hopefully, this is superior to the previous interpretations. It has, I believe, the advantage of logical clarity. In the process of doing this, I introduce a theory of levels of physical theory, according to which microscopic physical theory, as it develops in successive stages, becomes more and more adaptable to explaining—or at least taking cognizance of—fundamental biological or ultimately psychological phenomena.

Edward M. MacKinnon

O. L. S. Silva Filho, Samuel J. Simon, Marcello Caio Ramon e Barros Ferreira

When a physical theory is in its early stages of development, it presents many concepts and constructs that may not be necessary for its interpretation, or may simply be equivocal. As the theory is developed by the physics community, it hopefully passes through a depuration process that washes away many of these constructs and introduces others not initially devised. This process can be viewed, and modeled, as a semiotic process by which the suggested interpretations of the theory, initially dispersed in the space of concepts, taper off in a way that leaves only a small number of possibilities, ideally only one. However, to qualify this process and impose semiotic and epistemological constraints on the depuration process, it seems natural to consider a physical theory as an excerpt of a language and its suggested interpretations as texts, endowed with syntactics and semantics. In this paper we present this framing of general physical theories and apply the resulting semiotic and epistemological constraints we uphold to the special case of quantum mechanics, which shows particular resistance to interpretation tapering. We then show that the findings of this paper are especially important for allowing one to form a hierarchy of interpretations of the same formal structure of a physical theory, even in the case of an experimental underdetermination of these interpretations, which is precisely the case for quantum mechanics. This result is particularly important for more modern physical theories, which are becoming increasingly more abstract and difficult to interpret.

Erkki Brändas

Eugene Paul Wigner

Lawrence Sklar

Abstract If we take a comparative look at what goes on when a fundamental theory is said to be interpreted, I think there is little doubt that we will agree that ‘interpretation’ is a family-resemblance term. There may be some chain of relevant pairwise similarities that connect all the standard cases of interpretation into a chain, but there are plainly pairs of interpretations of theories that have few interesting common elements. A very wide range of theories have been subjected to interpretive programs. But in order to focus our attention it will be best to look just at those interpretations directed toward foundational theories in physics. Even with this restriction, we shall see, there is quite a diversity of things that goes on when one is said to be offering an interpretation of one of these fundamental physical theories.