Contemporary physics, especially quantum theory, has raised profound questions about the relationship between the methods of science and the reality these methods seek to investigate. D'Espagnat investigates these questions as well as how we should answer them. Part I examines the practices of contemporary physicists and addresses the criticism philosophers of science have made of these practices. The doctrine of physical realism, adopted by most physicists and many philosophers of science, comprises Part II. Part III explores the consequences of (...) physical realism for our understanding of what science can seek to know of reality, and concludes by outlining the position contemporary physics indicates we should take. (shrink)
Abstract. In the last decades, several rapprochements have been made between quantum physics and the Advaita Vedānta (AV) school of Hinduism. Theoretical issues such as the role of the observer in measurement and physical interconnectedness have been associated with tenets of AV, generating various critical responses. In this study, I propose to address this encounter in the light of recent works on philosophical implications of quantum physics by the physicist and philosopher of science Bernard d’Espagnat.
On Two Types of Realism in Quantum Theory. Current realist approaches to the foundations of quantum theory emphasize the dichotomy between (Copenhagen) positivism and ‘beable’-realism. Recently it was even attempted to turn this picture into two (equally possible) histories in order to legitimate Bohmian Mechanics as a viable alternative. This paper argues that this dichotomy is philosophically inadequate and historically questionable by embedding it into the philosophical discussion on positivism and realism that has taken place since the 1920s. Logical Empiricists (...) back then advocated empirical realism and contrasted it to absolutistic metaphysical realism. From this viewpoint David Bohm's ‘beable’-realism combines elements of Mach's sensualism with a pre-Kantian metaphysics. As Wesley Salmon's position shows, empirical realism can become quite pronounced without relapsing into Bohmian philosophy. Instead it arrives close to the GRWP-interpretation. Hence, when Bernard d'Espagnat binds both together as ‘ontological interpretations’, he blurs the borderline between empirical and metaphysical realism that his Veiled Reality has set out to draw, quite in concordance with Logical Empiricism. (shrink)
In the context of stochastic hidden variable theories, Howard has argued that the role of separability—spatially separated systems possess distinct real states—has been underestimated. Howard claims that separability is equivalent to Jarrett‘s completeness: this equivalence should imply that the Bell theorem forces us to give up either separability or locality. Howard's claim, however, is shown to be ill founded since it is based on an implausible assumption. The necessity of sharply distinguishing separability and locality is emphasized: a quantitative formulation of (...) separability, due to D'Espagnat, is reviewed and found unsatisfactory, in that it basically conflates separability and locality in a single notion. Finally, the possibility of an ‘Einsteinian’ nonseparable realism, envisaged by Shimony, is reviewed and found also to be implausible. (shrink)