Bell's Future Quantum Mechanics Interpretation

Hisato Shirai

The ensemble interpretation (EI) of quantum mechanics has been proposed by physicists and philosophers (e.g., A. Einstein, K. R. Popper, and A. Lande). However, it is not accepted widely among modern scientists. This is because the EI is regarded as a kind of the hidden variable theories. The scientists believe that the EI is inconsistent with violation of Bell's inequalities. The present paper points out that there are various types of the EI. Several of them can be consistent with the violation. The non-local type of the EI proposed by Shirai in 1998 is also consistent. We call it “holistic ensemble interpretation (HEI).” The non-locality in the HEI includes a temporal non-locality (i.e., a future dependence), implying that the present distributions depend on the future conditions. The concept of the future dependence would be so controversial that we discuss it deeply in the latter half of the paper. Many scientists may think of it as a doubtful concept, because it disagrees with the concept of “free will.” However, there are several reasons why we should consider the future dependence.

Roland L. Omnes

Silvester Sabathiel

Hilary Putnam

David Albert has proved an important theorem, a surprising one, which certainly has relevance to the way we will understand quantum mechanics in the future. Whether its moral is really the “non-narratibility” of the history of the quantum world is, however, dependent on interpretative questions about which philosophers and physicists – even philosophers and physicists who, like David Albert and myself, are looking for what the late, great, J. S. Bell called an “unromantic” interpretation of quantum mechanics – are sure to disagree. In this brief comment I want to say what Albert has certainly shown , and what depends on those interpretative questions (and, of course, what those questions are). By an “unromantic” interpretation, what Bell meant is an intelligible and mathematically precise interpretation in which there is no talk about “consciousness” reducing the wave packet, “measurements” are simply described as a subclass of physical interactions, and, of course, there is no loose talk about the world consisting of “information.”

Huw Price

Bell's Theorem assumes that hidden variables are not influenced by future measurement settings. The assumption has sometimes been questioned, but the suggestion has been thought outlandish, even by the taxed standards of the discipline. (Bell thought that it led to fatalism.) The case for this reaction turns out to be surprisingly weak, however. We show that QM easily evades the standard objections to advanced action. And the approach has striking advantages, especially in avoiding the apparent conflict between Bell's Theorem and special relativity. The second part of the paper considers the broader question as to why advanced action seems so counterintuitive. We investigate the origins of our ordinary intuitions about causal asymmetry. It is argued that the view that the past does not depend on the future is largely anthropocentric, a kind of projection of our own temporal asymmetry. Many physicists have also reached this conclusion, but have thought that if causation has no objective direction, there is no objective content to an advanced action interpretation of QM. This turns out to be a mistake. From the ordinary subjective perspective, we can distinguish two sorts of objective world: one "looks as if" it contains only forward causation, the other ``looks as if'' it involves a mix of backward and forward causation. This clarifies the objective core of an advanced action interpretation of QM, and shows that there is an independent symmetry argument in favour of the approach.

Jochen Pade