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arXiv · 1403.3858

Geodesics dynamics in the Linet-Tian spacetime with Lambda<0

Irene Brito·M. F. A. da Silva·Filipe C. Mena·N. O. Santos
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Abstract

We investigate the geodesics' kinematics and dynamics in the Linet-Tian metric with Lambda<0 and compare with the results for the Levi-Civita metric, when Lambda=0. This is used to derive new stability results about the geodesics' dynamics in static vacuum cylindrically symmetric spacetimes with respect to the introduction of Lambda<0. In particular, we find that increasing |Lambda| always increases the minimum and maximum radial distances to the axis of any spatially confined planar null geodesic. Furthermore, we show that, in some cases, the inclusion of any Lambda<0 breaks the geodesics' orbit confinement of the Lambda=0 metric, for both planar and non-planar null geodesics, which are therefore unstable. Using the full system of geodesics' equations, we provide numerical examples which illustrate our results.

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Irene Brito, M. F. A. da Silva, Filipe C. Mena, N. O. Santos. 2014-03-15. Geodesics dynamics in the Linet-Tian spacetime with Lambda<0. https://doi.org/10.1007/s10714-014-1681-7

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