What Is the Quantum Face of Realism?

Linda Wessels

James Ladyman, Lorenzo Lorenzetti

Three accounts of effective realism (ER) have been advanced to solve three problems for scientific realism: Fraser and Vickers (forthcoming) develop a version of ER about non-relativistic quantum mechanics that they argue is compatible with all the main realist versions (‘interpretations’) of quantum mechanics avoiding the problem of underdetermination among them; Williams (2019) and Fraser (2020b) propose ER about quantum field theory as a response to the problems facing realist interpretations; Robertson and Wilson (forthcoming) propose ER to deal with the dubious ontological status of the entities belonging to superseded theories. This paper argues for the unification of these proposals based on realism about modal structure and the idea of scale relativity of ontology developed by ontic structural realists. This solves problems some or all the accounts of ER face, especially that of making explicit in what way they are realist. Furthermore, we respond to a recent critique that has been raised against the ontic structural realist account of quantum mechanics that we employ.

Juha T. Saatsi

Scientific realism about spin is easily motivated. But what does it amount to? To answer this question, Chapter 3 contrasts in general terms two epistemological conceptions of realism—truth-content vs. progress realism—before problematizing truth-content realism in the context of quantum physics. After articulating the challenge faced by truth-content realism, the chapter argues that progress realism avoids it, offering a stable middle ground between anti-realism and traditional truth-content realism.

G. C. Ghirardi

G. C. Ghirardi