Strong gravitational lensing in a black-hole spacetime dominated by dark energy

TL;DR

This paper investigates how phantom dark energy fields influence strong gravitational lensing around black holes, revealing effects similar to electric charge but also unique dark energy signatures that could aid observational detection.

Contribution

It introduces a phantom black hole model to analyze dark energy effects on gravitational lensing, highlighting observable differences from standard black holes.

Findings

Phantom fields increase deflection angles and Einstein ring sizes.

Dark energy effects resemble electric charge influences but have distinct observational signatures.

Dark energy causes stronger photon attraction and larger relativistic rings.

Abstract

We study the influence of phantom fields on strong field gravitational lensing. Supposing that the gravitational field of the supermassive central object of the Galaxy is described by a phantom black hole metric, we estimate the numerical values of the coefficients and observations and find that the influence of the phantom fields is somewhat similar to that of the electric charge in a Reissner-Norstr\"{o}m black hole, i.e., the deflect angle and angular separation increase with the phantom constant $b$. However, other observations are contrary to the Reissner-Norstr\"{o}m case and show the effects of dark energy, such as (i) compressing the usual black hole and more powerfully attracting photons, (ii) making the relativistic Einstein ring larger than that of the usual black hole, and (iii) not weakening the usual relative magnitudes, which will facilitate observations.