Gravitational lensing by a Horndeski black hole

TL;DR

This paper investigates gravitational lensing effects caused by non-rotating black holes in Horndeski theory, calculating deflection angles and image properties, and compares these with predictions from General Relativity, highlighting potential astrophysical implications.

Contribution

It provides the first detailed analysis of strong deflection lensing by Horndeski black holes and compares results with GR, revealing possible observational differences.

Findings

Deflection angles calculated in Horndeski theory differ from GR predictions.

Relativistic image positions and magnifications are quantified.

Astrophysical implications for supermassive black holes are discussed.

Abstract

In this article we study gravitational lensing by non-rotating and asymptotically flat black holes in Horndeski theory. By adopting the strong deflection limit, we calculate the deflection angle, from which we obtain the positions and the magnifications of the relativistic images. We compare our results with those corresponding to black holes in General Relativity. We analyze the astrophysical consequences in the case of the nearest supermassive black holes.