# Renormalizability, fundamentality and a final theory: The role of UV-completion in the search for quantum gravity

## TL;DR

The paper critically examines the role of UV completion as a guiding principle in the search for quantum gravity, arguing it is poorly motivated and not a reliable criterion for theory justification.

## Contribution

It challenges the widespread assumption that UV completion should guide quantum gravity research and analyzes its proper role in theory development.

## Key findings

- UV completion is not well-motivated as a guiding principle.
- UV completion cannot serve as a criterion for theory justification.
- The paper offers a critical analysis of how UV completion is used in quantum gravity approaches.

## Abstract

Principles are central to physical reasoning, particularly in the search for a theory of quantum gravity (QG), where novel empirical data is lacking. One principle widely adopted in the search for QG is UV completion: the idea that a theory should (formally) hold up to all possible high energies. We argue---\textit{contra} standard scientific practice---that UV-completion is poorly-motivated as a guiding principle in theory-construction, and cannot be used as a criterion of theory-justification in the search for QG. For this, we explore the reasons for expecting, or desiring, a UV-complete theory, as well as analyse how UV completion is used, and how it should be used, in various specific approaches to QG.