Slowly decaying waves on spherically symmetric spacetimes and ultracompact neutron stars
By Joseph Keir. 2014
160 citations recorded by the source corpus.
We prove that, in a class of spherically symmetric spacetimes exhibiting stable trapping of null geodesics, linear waves cannot (uniformly) decay faster than logarithmically. When these linear waves are treated as a model for nonlinear perturbations, this slow decay is highly suggestive of nonlinear instability. We also prove that, in a large class of asymptotically flat, spherically symmetric spacetimes, logarithmic decay actually holds as a uniform upper bound. In the presence of stable trapping, this result is therefore the best one can obtain. In addition, we provide an application of these results to ultracompact neutron stars, suggesting that all stars with r < 3 M might be unstable.
Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics
View Paper: https://www.semanticscholar.org/paper/7b105700eb1d24bebd1f3f6294bba60de40821d7
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Astronomy and Astrophysics
- Paolo Pani
- R. Brito
- V. Cardoso
- Carlos A. R. Herdeiro
- P. Cunha
- Eugen Radu
- N. Sanchis-Gual
- Alexandre M. Pombo
In Nuclear and High Energy Physics
- R. Brito
- Paolo Pani
- V. Cardoso
- P. Cunha
- Carlos A. R. Herdeiro
- Eugen Radu
- N. Sanchis-Gual
- Alexandre M. Pombo
Citations in the corpus
- Superradiance (2015, background): “Being trapped between the center of the object and the light ring, and being localized near a second, stable null geodesic [566, 743], the long damping time of these modes has led to the conjecture that ECOs are nonlinearly unstable and may evolve through a Dyson-Chandrasekhar-Fermi type of mechanis”
- Tests for the existence of black holes through gravitational wave echoes (2017, background): “Linearized gravitational fluctuations of any nonspinning UCO are extremely longlived and decay no faster than logarithmically [30, 31].”
- Shadows and strong gravitational lensing: a brief review (2018, background): “This intuition was reinforced in a paper by Keir [26], in which the existence of a stable LR sets a decay limit for linear waves, being highly suggestive of a non-linear instability.”
- The imitation game: Proca stars that can mimic the Schwarzschild shadow (2021, background): “Such stable LRs have been argued to lead to a non-perturbative instability [59–61].”