On the Impossibility of Precise Verification of Models of Quantum Gravity

TL;DR

This paper argues that it is fundamentally impossible to verify models of quantum gravity with arbitrary precision within a finite causal region, impacting the scientific testability of such theories in our universe.

Contribution

It introduces a theoretical limitation on the verifiability of quantum gravity models in finite regions, especially in de Sitter universes, highlighting fundamental constraints on empirical testing.

Findings

No model of quantum gravity in a finite boundary can be verified with arbitrary precision.

In an asymptotically de Sitter universe, no information system can distinguish between competing models.

The result emphasizes fundamental limits on empirical access to quantum gravity theories.

Abstract

We argue that no theoretical model of quantum gravity in a causal diamond whose boundary has finite maximal area, can be verified with arbitrary precision by experiments done in that diamond. This shows in particular that if our own universe remains in an asymptotically future de Sitter state for a time long enough for our local group of galaxies to collapse into a black hole, then no information processing system with which we can communicate could ever distinguish between many competing models of the AsdS universe. This article is written in an attempt to be accessible to a wide audience, so certain elementary facts about quantum mechanics are reviewed, briefly.