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arXiv · 2305.15450

Revisiting Weak Energy Condition and wormholes in Brans-Dicke gravity

Hoang Ky Nguyen·Mustapha Azreg-Aïnou
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Abstract

It is known that the formation of a wormhole typically involves a violation of the Weak Energy Condition (WEC), but the reverse is not necessarily true. In the context of Brans-Dicke gravity, the $\textit{generalized}$ Campanelli-Lousto solution, which we shall unveil in this paper, demonstrates a WEC violation that coincides with the appearance of $\textit{unbounded}$ sheets of spacetime within the "interior" section. The emergence of a wormhole in the "exterior" section is thus only an indirect consequence of the WEC violation. Additionally, we use the generalized Campanelli-Lousto solution to construct a Kruskal-Szekeres diagram, which exhibits a "gulf" sandwiched between the four quadrants in the diagram, a novel feature in Brans-Dicke gravity. Overall, our findings shed new light onto a complex interplay between the WEC and wormholes in the Brans-Dicke theory.

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Hoang Ky Nguyen, Mustapha Azreg-Aïnou. 2024-10-07. Revisiting Weak Energy Condition and wormholes in Brans-Dicke gravity. https://doi.org/10.1016/j.nuclphysb.2024.116669

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