The emergence and interpretation of probability in Bohmian mechanics

A persistent question about the deBroglie–Bohm interpretation of quantum mechanics concerns the understanding of Born's rule in the theory. Where do the quantum mechanical probabilities come from? How are they to be interpreted? These are the problems of emergence and interpretation. In more than 50 years no consensus regarding the answers has been achieved. Indeed, mirroring the foundational disputes in statistical mechanics, the answers to each question are surprisingly diverse. This paper is an opinionated survey of this literature. While acknowledging the pros and cons of various positions, it defends particular answers to how the probabilities emerge from Bohmian mechanics and how they ought to be interpreted.     

Hemodynamic studies in the circle of willis in the rat

Résumé Les changements de tension artérielle dans l'artère linguale des Rats ont été mesurés après l'occlusion des artères carotidiennes et vertébrales. Les données obtenues nous font supposer que les artères vertébrales sont en grande partie responsables du maintient de la tension artérielle dans le cerveau.     

Squaring the circle: Gleb Wataghin and the prehistory of quantum gravity

The early history of the attempts to unify quantum theory with the general theory of relativity is depicted through the work of the Italian physicist Gleb Wataghin, who, in the context of quantum electrodynamics, has anticipated some of the ideas that the quantum gravity community is entertaining today.     

Paul Natorp and the emergence of anti-psychologism in the nineteenth century

This paper examines the anti-psychologism of Paul Natorp, a Marburg School Neo-Kantian. It identifies both Natorp’s principle argument against psychologism and the views underlying the argument that give it its force. Natorp’s argument depends for its success on his view that certain scientific laws constitute the intersubjective content of knowledge. That view in turn depends on Natorp’s conception of subjectivity, so it is only against the background of his conception of subjectivity that his reasons for rejecting psychologism make sense. This interpretation of Natorp suggests that attention paid to late nineteenth century theories of subjectivity and philosophy of psychology could improve our understanding of the emergence of anti-psychologism in that period.     

Reduction and emergence in the fractional quantum Hall state

We present the fractional quantum Hall (FQH) effect as a candidate emergent phenomenon. Unlike some other putative cases of condensed matter emergence (such as thermal phase transitions), the FQH effect is not based on symmetry breaking. Instead FQH states are part of a distinct class of ordered matter that is defined topologically. Topologically ordered states result from complex long-ranged correlations between their constituent parts, such that the system displays strongly irreducible, qualitatively novel properties.