Fact-nets: towards a mathematical framework for relational quantum mechanics

The relational interpretation of quantum mechanics (RQM) has received a growing interest since its first formulation in 1996. Typically perceived as an interpretational layer on the existing quantum mechanics framework, RQM is often seen merely as a philosophical stance lacking proper mathematical foundations. This limitation hinders scientific discussion on RQM, leading to misunderstandings and vague assertions. To address these issues, this paper introduces a transformative reformulation of the mathematical framework of quantum mechanics, termed fact-nets, which adopts a relational perspective from the outset. The central concept is that all statements regarding the world—referred to as facts—are binary constructs involving two systems that can be symmetrically viewed as observer and observed. The study initiates an exploration of the fact-nets formalism and illustrates its potential for offering a fresh relational perspective on familiar quantum phenomena.