# Astronomical tests for quantum black hole structure

## TL;DR

This paper reviews potential observational tests, such as gravitational waves and interferometry, to detect quantum modifications of black holes that challenge classical descriptions and reconcile them with quantum mechanics.

## Contribution

It provides an overview of possible observational methods to test quantum black hole structures, highlighting avenues for future empirical investigation.

## Key findings

- Gravitational wave detection can reveal quantum black hole signatures.
- Very long baseline interferometry offers potential tests for horizon-scale quantum effects.
- Current observational techniques could distinguish between classical and quantum black hole models.

## Abstract

Quantum modifications to black holes on scales comparable to the horizon size, or even more radical physics, are apparently needed to reconcile the existence of black holes with the principles of quantum mechanics. This piece gives an overview of some possible observational tests for such departures from a classical description of black holes, via gravitational wave detection and very long baseline interferometry. (Invited comment for Nature Astronomy.)