Bose-Einstein condensed supermassive black holes: a case of renormalized quantum field theory in curved space-time

TL;DR

This paper explores a model where supermassive black holes are described as Bose-Einstein condensates of hydrogen atoms within a quantum field theory framework in curved spacetime, proposing a new perspective on black hole structure.

Contribution

It introduces a self-consistent solution for a supermassive black hole modeled as a Bose-Einstein condensate with a specific coupling, linking quantum field theory to black hole physics.

Findings

Black holes can have a 'hair' in the form of binding energy.

A specific coupling parameter $\xi$ is identified for the condensate state.

The model suggests a finite redshift at the horizon, making black holes similar to stars.

Abstract

This paper investigates the question whether a realistic black hole can be in principal similar to a star, having a large but finite redshift at its horizon. If matter spreads throughout the interior of a supermassive black hole with mass $M\sim10^9M_\odot$, it has an average density comparable to air and it may arise from a Bose-Einstein condensate of densely packed H-atoms. Within the Relativistic Theory of Gravitation with a positive cosmological constant, a bosonic quantum field describing H atoms is coupled to the curvature scalar with dimensionless coupling $\xi$. In the Bose-Einstein condensed groundstate an exact, self-consistent solution for the metric occurs for a certain large value of $\xi$, quadratic in the black hole mass. It is put forward that $\xi$ is set by proper choice of the background metric as a first step of a renormalization approach, while otherwise the non-linearities are small. The black hole has a hair, the binding energy. Fluctuations about the ground state are considered.