Tension in Bohm’s Interpretation of Quantum Mechanics

Abstract

David Bohm and his predecessor Louis de Broglie (1927) were exploratory men, each of whom proposed and examined a number of theories. Their various theories shared some central ideas but also differed in significant respects, and an assessment of all of these variant theories is beyond the scope of this paper. We shall mainly restrict our attention to what we shall call “Rohm’s initial theory,” which was presented in his pioneering papers (Bohm 1952a,b), and in two letters (Bohm 1952c; 1953a) and a paper (Bohm 1953b) which clarified and defended his initial presentation. Our main thesis is that two different physical views coexist uneasily in Bohm’s initial theory, which we shall call “the causal view” and “the guidance view.” We shall cite passages indicating that he was aware of this fact and that he pondered ways of relieving the tension between the two views. Because of the great historical importance of Bohm’s initial theory, there is obviously value in a careful explication de texte. In addition, however, we have a conceptual thesis: that what makes Bohm’s initial theory attractive philosophically and scientifically is a conjunction of some features of the causal view and some of the guidance view. We shall present some reasons for skepticism about the prospects for a coherent combination of the two views. We shall also note that some of the most influential advocates of Bohmian mechanics — including Dürr et al. (1992a), Valentini (1991a), and Cushing (1994) — treat the tension between the two views in the initial theory of Bohm by surgery, for they retain the guidance view and discard whatever of the causal view is incompatible with it. We shall not undertake to assess these recent expositions of Bohmian mechanics, because of mathematical difficulties which we find very formidable, but we shall express some skeptical doubts in hope of evoking clarifications and amplifications from the authors.

This paper is dedicated with deep appreciation to Professor Hans Primas on the occasion of his retirement from the ETH.