Stable Facts, Relative Facts

TL;DR

This paper explores how stable facts emerge from relative facts in quantum systems, clarifying their role in connecting quantum theory with the classical world and resolving foundational paradoxes.

Contribution

It introduces a framework distinguishing stable and relative facts, explaining their emergence and resolving key quantum paradoxes like the no-go theorems.

Findings

Stable facts can be effectively isolated from relative facts.

The framework clarifies decoherence's role in classical emergence.

It resolves incompatibilities between linear evolution and projection in quantum theory.

Abstract

Facts happen at every interaction, but they are not absolute: they are relative to the systems involved in the interaction. Stable facts are those whose relativity can effectively be ignored. In this work, we describe how stable facts emerge in a world of relative facts and discuss their respective roles in connecting quantum theory and the world. The distinction between relative and stable facts resolves the difficulties pointed out by the no-go theorems of Frauchiger and Renner, Brukner, Bong et. al.. Basing the ontology of the theory on relative facts clarifies the role of decoherence in bringing about the classical world and solves the apparent incompatibility between the `linear evolution' and `projection' postulates.