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arXiv · 1811.08245

A novel gravitational lensing feature by wormholes

Rajibul Shaikh·Pritam Banerjee·Suvankar Paul·Tapobrata Sarkar
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Abstract

Horizonless compact objects with light rings (or photon spheres) are becoming increasingly popular in recent years for several reasons. In this paper, we show that a horizonless object such as a wormhole of Morris-Thorne type can have two photon spheres. In particular, we show that, in addition to the one present outside a wormhole throat, the throat can itself act as an effective photon sphere. Such wormholes exhibit two sets of relativistic Einstein ring systems formed due to strong gravitational lensing. We consider a previously obtained wormhole solution as a specific example. If such type of wormhole casts a shadow at all, then the inner set of the relativistic Einstein rings will form the outer bright edge of the shadow. Such a novel lensing feature might serve as a distinguishing feature between wormholes and other celestial objects as far as gravitational lensing is concerned.

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Rajibul Shaikh, Pritam Banerjee, Suvankar Paul, Tapobrata Sarkar. 2018-12-31. A novel gravitational lensing feature by wormholes. https://doi.org/10.1016/j.physletb.2018.12.030

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