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arXiv · 2108.09930

Shadows of Lorentzian traversable wormholes

Farook Rahaman·Ksh. Newton Singh·Rajibul Shaikh·Tuhina Manna·Somi Aktar
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Abstract

The prospect of identifying wormholes by investigating the shadows of wormholes constitute a foremost source of insight into the evolution of compact objects and it is one of the essential problems in contemporary astrophysics. The nature of the compact objects (wormholes) plays a crucial role on shadow effect, which actually arises during the strong gravitational lensing. Current Event Horizon Telescope observations have inspired scientists to study and to construct the shadow images of the wormholes. In this work, we explore the shadow cast by a certain class of rotating wormhole. To search this, we first compose the null geodesics and study the effects of the parameters on the photon orbit. We have exposed the form and size of the wormhole shadow and have found that it is slanted as well as can be altered depending on the different parameters present in the wormhole spacetime. We also constrain the size and the spin of the wormhole using the results from M87* observation, by investigating the average diameter of the wormhole as well as deviation from circularity with respect to the wormhole throat size. In a future observation, this type of study may help to indicate the presence of a wormhole in a galactic region.

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Farook Rahaman, Ksh. Newton Singh, Rajibul Shaikh, Tuhina Manna, Somi Aktar. 2021-10-31. Shadows of Lorentzian traversable wormholes. https://doi.org/10.1088/1361-6382%2Fac213b

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