相关论文: Spacetime Measurements with the Photon Ring
Light propagating through a perturbed spacetime could imprint the underlying gravitational waveform directly onto electromagnetic observables. In this Letter, we develop a covariant perturbative framework for polarized photon propagation in…
General relativity predicts that images of optically thin accretion flows around black holes should generically have a ``photon ring,'' composed of a series of increasingly sharp subrings that correspond to increasingly strongly lensed…
We have studied numerically the shadows of a non-Kerr rotating compact object with quadrupole mass moment, which belongs to Manko-Novikov family. The non-integrable photon motion caused by quadrupole mass moment affects sharply the shadow…
The space-time geometry under investigation is chosen to be a high-dimensional, static, spherically symmetric solution in an asymptotically flat background within the Einstein-power-Yang-Mills-Gauss-Bonnet (EPYMGB) gravity. To address the…
We investigate the temperature, photon and shadow radii, quasinormal modes (QNMs), time domain profiles, greybody factors, emission rates and topological characteristics of deformed black holes, focusing on the effects of the deformation…
The first image of black hole in M87 galaxy taken by Event Horizon Telescope shows that directed observation of supermassive black holes would be a promising way to test general relativity in strong gravity field regime. In order to…
We study the shadow of rotating charge black holes in the presence of quintessence. The shadow of a rotating black hole is a distorted circle and in our study, we find that the shape and size of the black hole shadow depend upon four…
This study investigates the quasinormal modes of Kerr-Newman-de Sitter black holes for massless spin particles using the unified equation. We derive analytical expressions for both the quasinormal mode frequencies and the radial wave…
The photon sphere, a hypersurface of null circular geodesics, plays a fundamental role in characterizing black hole spacetimes, influencing phenomena such as black hole shadows, gravitational lensing, and quasinormal modes. In this work, we…
In this work, we investigate the relationship between the photon sphere radius and the first-order phase transition for the charged EPYM AdS black hole. Through the analysis, we find with a certain condition there exist the non-monotonic…
We investigate the finite-time instability of massive spinning test particles around a rotating hairy black hole generated through gravitational decoupling. The particle motion is described by the full Mathisson-Papapetrou-Dixon equations…
We investigate black holes with non-minimal couplings between the electromagnetic field and spacetime curvature, focusing on their event horizons, shadows, and photon rings. Such couplings can naturally arise from both classical effective…
We study the time delay between successive relativistic images in gravitational lensing as a possible discriminator between various collapse end states and hence as a probe of cosmic censorship. Specifically we consider both black hole and…
Plasma, as a medium around the black hole for light propagation, is known to visibly alter the shape of its shadow and the observables, which could impact the interpretation of the Event Horizon Telescope results. In this study, we examine…
In this paper, we study the shadow and images of the accretion disk of Kerr-Newman (KN) black hole (BH) in modified gravity (MOG) theory by using backward ray-tracing method. And, the influence of spin parameter ($a$), charge ($Q$), and MOG…
We study the accretion process in the thin disk around a rotating non-Kerr black hole with a deformed parameter and an unbound rotation parameter. Our results show that the presence of the deformed parameter $\epsilon$ modifies the standard…
Gravitational lensing near a black hole is strong enough that light rays can circle the event horizon multiple times. Photons emitted in multiple directions at a single event, perhaps because of localized, impulsive heating of accreting…
General relativity predicts the spacetime metric around an astrophysical black hole to be described by the Kerr solution, which is a massive rotating black hole without any residual charge. In a previous paper, we analyzed the NuSTAR…
We study spherically symmetric magnetically charged generic black hole solutions of general relativity coupled to non-linear electrodynamics (NED). For characteristic values of the generic spacetime parameters we give the position of…
The Event Horizon Telescope (EHT) has provided a new tool for testing the strong-field regime of gravity by imaging the shadows of M87* and Sgr A*. These observations provide the first real opportunity to test whether quantum…