Events

The Open Systems View

A standard assumption in quantum theory is that closed, isolated systems are fundamental, while open systems are merely effective descriptions obtained by embedding them into larger closed systems. In this talk, I challenge this assumption and develop the open systems view, according to which systems interacting with their environments can themselves be treated as fundamental. The physical motivation is straightforward: in many central areas of contemporary physics—decoherence, quantum thermodynamics, cosmology, and black hole physics—strict isolation is neither realistic nor conceptually well defined. I outline a general framework for open quantum dynamics in which environmental influence is represented directly in the system’s dynamical laws, without presupposing an underlying unitary system–environment decomposition. I then connect this framework to foundational debates by showing how standard interpretations of quantum mechanics—both orthodox (Bohr-style) and (neo-)Everettian—are, despite appearances, already ontologically committed to open systems. The open systems view thus suggests a reorientation of how we think about fundamentality, interpretation, and the role of idealization in quantum theory, and offers a philosophically illuminating perspective on what quantum theory is fundamentally about.

The talk is based on joint work with Michael E. Cuffaro (MCMP).

Zoom

Monday, February 9, 2026 11:00 AM

Inperson
BHI Conference Room and Zoom