Optical appearance of a thin-shell wormhole with a Hayward profile

TL;DR

This paper explores the optical effects of a Hayward-profile thin-shell wormhole, revealing unique light reflection and lensing features, including additional photon rings, influenced by the mass ratio of black holes.

Contribution

It introduces the optical properties of a Hayward-profile thin-shell wormhole using ray-tracing, highlighting how mass ratios affect light trajectories and observable features.

Findings

Significant light reflection back to the observer spacetime.

Presence of additional photon rings and lensing bands.

Photon trajectories exhibit round-trip behavior under certain conditions.

Abstract

The optical properties of a thin-shell wormhole (TSW) with a Hayward profile is investigated. Adopting the ray-tracing method, we demonstrate that the TSW's contralateral spacetime is capable of reflecting a significant portion of light back to the observer spacetime. We analyze the effective potential, light deflection, and azimuthal angle of the TSW and find that these quantities are affected by the mass ratio of the black holes (BHs). Specifically, if the mass of the contralateral spacetime BH is greater than that of the original spacetime BH, and the impact parameter satisfies the condition $Hb_{\rm c2}<b_{1}<b_{\rm c1}$, the trajectory of the photon exhibits round-trip characteristics. Assuming the presence of a thin accretion disk surrounding the observing spacetime BH, our results indicate that the image formed by the TSW exhibits additional photon rings and a lensing band compared to an image produced by a BH alone.