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arXiv · 2312.17559

Shadow of a collapsing star in a regular spacetime

Daniel Nunez·Juan Carlos Degollado
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Abstract

We describe the dynamical formation of the shadow of a collapsing star in a Hayward spacetime in terms of an observer far away from the center and a free falling observer. By solving the time-like and light-like radial geodesics we determine the angular size of the shadow as a function of time. We found that the formation of the shadow is a finite process for both observers and its size is affected by the Hayward spacetime parameters. We consider several scenarios, from the Schwarzschild limit to an extreme Hayward black hole.

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Daniel Nunez, Juan Carlos Degollado. 2023-12-29. Shadow of a collapsing star in a regular spacetime. https://arxiv.org/abs/2312.17559

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