New approach to conserved charges of generic gravity in AdS spacetimes

Altaş Kiracı, Emel
Tekin, Bayram
Neutron stars constitute an important class of extreme relativistic objects allowing one to examine the theories of gravitation in the strong field regime. Their supranuclear densities stemming from their large masses and small radii make them also interesting laboratories for matter under extreme conditions which is modelled by different equations of states (EoS). Such extreme conditions make the determination of EoS a difficult problem in nuclear physics but, on the other hand, the studies in this direction may allow, for example, to constrain even dark matter models in a way that is inaccessible to terrestrial or cosmological probes. We study the structure of neutron stars in a special class of the scalar-tensor theories for three realistic EoS and the Higgs-like potential. Using the observational bounds on the mass and the radius of the neutron stars, we put some limits on the parameters of the model.


New approach to conserved charges of generic gravity in AdS spacetimes
Altas, Emel; Tekin, Bayram (American Physical Society (APS), 2019-02-12)
Starting from a divergence-free rank-4 tensor of which the trace is the cosmological Einstein tensor, we give a construction of conserved charges in Einstein's gravity and its higher derivative extensions for asymptotically anti-de Sitter spacetimes. The current yielding the charge is explicitly gauge invariant, and the charge expression involves the linearized Riemann tensor at the boundary. Hence, to compute the mass and angular momenta in these spacetimes, one just needs to compute the linearized Riemann...
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Citation Formats
E. Altaş Kiracı and B. Tekin, “New approach to conserved charges of generic gravity in AdS spacetimes,” presented at the 17th Workshop on Quantization, Dualities and Integrable Systems, 2019, Accessed: 00, 2021. [Online]. Available: