Spacetime emergence: an (in)effective story

TL;DR

The paper critically examines the idea of spacetime as an effective description in physics, arguing that general relativity's global content challenges the notion of spacetime emergence as purely effective.

Contribution

It clarifies the limitations of viewing general relativity as an effective theory and questions the common interpretation of spacetime emergence in quantum gravity.

Findings

General relativity includes irreducible global physical content.

This global content challenges the effective description view.

The interpretive scope of spacetime emergence is more limited than previously thought.

Abstract

Physicists and philosophers are increasingly prone to regarding our current physical theories as providing 'effective descriptions' of real-world systems. In the context of quantum gravity research, this fuels a common view that the classical spacetime theory of general relativity provides effective descriptions where it is successfully applied. That common view of general relativity, in turn, encourages an 'effective' understanding of spacetime emergence. But descriptions of spacetime in general relativity irreducibly include global physical content, which is not effective. Recognizing this fact reigns in the interpretive scope of the common view of general relativity and specifically undermines our thinking about spacetime emergence effectively.