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arXiv · 1612.09215

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 analyse the geodesics' dynamics in cylindrically symmetric vacuum spacetimes with Lambda>0 and compare it to the Lambda=0 and Lambda<0 cases. When Lambda>0 there are two singularities in the metric which brings new qualitative features to the dynamics. We find that Lambda=0 planar timelike confined geodesics are unstable against the introduction of a sufficiently large Lambda, in the sense that the bounded orbits become unbounded. In turn, any non-planar radially bounded geodesics are stable for any positive Lambda. We construct global non-singular static vacuum spacetimes in cylindrical symmetry with Lambda>0 by matching the Linet-Tian metric with two appropriate sources.

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Irene Brito, M. F. A. Da Silva, Filipe C. Mena, N. O. Santos. 2016-12-29. Geodesics dynamics in the Linet-Tian spacetime with Lambda>0. https://doi.org/10.1088/0264-9381%2F32%2F18%2F185015

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