Scalar-tensor black holes in an expanding universe

TL;DR

This review explores scalar-tensor gravity models, focusing on black holes in expanding universes, highlighting their local geometry independence from cosmic expansion and identifying key features and gaps in current understanding.

Contribution

It synthesizes current knowledge on scalar-tensor black holes in expanding universes and emphasizes the common features and unresolved issues in the field.

Findings

Local black hole geometry often remains unaffected by cosmic expansion

Scalar-tensor models exhibit common features in black hole solutions

Identifies gaps in the understanding of black holes in scalar-tensor gravity

Abstract

In this review we focus our attention on scalar-tensor gravity models and their empirical verification in terms of black hole and wormhole physics. We focus on a black hole, embedded in an expanding universe, describing both cosmological and astrophysical scales. We show that in scalar-tensor gravity it is quite common that the local geometry is isolated from the cosmological expansion, so that it does not backreact on the black hole metric. We try to extract common features of scalar-tensor black holes in an expanding universe and point out the gaps that must be filled.