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arXiv · 2305.08082

Tidal forces in the Simpson-Visser black-bounce and wormhole spacetimes

Dhruv Arora·Parth Bambhaniya·Dipanjan Dey·Pankaj S. Joshi
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Abstract

The concept of regular black holes has gained attention in recent years, especially in the context of quantum gravity theories. In these theories, the existence of singularities is paradoxical as they represent a breakdown of the laws of physics. Motivated by the recent developments in this area, we study the tidal force effects in one such family of regular geometries described by the Simpson-Visser metric. We find the radial and angular force profiles for a radially in-falling particle in this spacetime and calculate the variation of the geodesic separation vector with the radial coordinate using two different initial conditions. These results are then compared with that of Schwarzschild black hole spacetime. We show that for a regular black hole, both radial and angular tidal forces show a peak outside the horizon and then fall to ultimately switch their behavior from stretching to compression and vice-versa. Also, they are finite at $r=0$ unlike the Schwarzschild spacetime. It is also seen that the angular deviation profile shows an oscillating behavior for a particular initial condition. Our analysis can be used to distinguish between regular black hole, one-way and two-way wormholes and a singular black hole spacetimes.

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Dhruv Arora, Parth Bambhaniya, Dipanjan Dey, Pankaj S. Joshi. 2023-05-14. Tidal forces in the Simpson-Visser black-bounce and wormhole spacetimes. https://arxiv.org/abs/2305.08082

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