# Black hole information problem and quantum gravity

## TL;DR

This paper explores the black hole information paradox within a quantum gravity framework, analyzing matter-gravity entanglement and non-unitary evolution in gravitational collapse.

## Contribution

It constructs canonical operators for a gravity-scalar system and discusses implications for information loss in quantum gravity.

## Key findings

- Matter-gravity entanglement is inherent in physical states.
- Matter fields alone exhibit non-unitary evolution.
- A successful quantum gravity theory would resolve information loss.

## Abstract

The gravity-scalar field system in spherical symmetry provides a natural setting for exploring gravitational collapse and its aftermath in quantum gravity. In a canonical approach, we give constructions of the constraint and Hamiltonian operators. Matter-gravity entanglement is an inherent feature of physical states, whether or not there is a black hole. Matter fields alone are an open system with a non-unitary evolution. However, if there is a successful theory of quantum gravity, there is no information loss.