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Dynamical stability of fluid spheres in spacetimes with a nonzero cosmological constant

Stanislav Hledik·Zdenek Stuchlik·Kristina Mrazova
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Abstract

The Sturm-Liouville eigenvalue equation for eigenmodes of the radial oscillations is determined for spherically symmetric perfect fluid configurations in spacetimes with a nonzero cosmological constant and applied in the cases of configurations with uniform distribution of energy density and polytropic spheres. It is shown that a repulsive cosmological constant rises the critical adiabatic index and decreases the critical radius under which the dynamical instability occurs.

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Stanislav Hledik, Zdenek Stuchlik, Kristina Mrazova. 2007-01-15. Dynamical stability of fluid spheres in spacetimes with a nonzero cosmological constant. https://doi.org/10.1142/9789812834300_0097

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