相关论文: Multi-probe analysis of strong-field effects in $f…
We employ Bozza's method to calculate the deflection angle of light in the presence of the strong gravitational field generated by an improved Schwarzschild-like black hole whose metric, regular throughout the entire spacetime, was derived…
Effective field theory (EFT) provides a systematic framework for parametrizing possible higher-energy corrections to general relativity through higher-curvature interactions. In this work, we investigate gravitational lensing in both weak-…
The 2017 Event Horizon Telescope (EHT) observations of the central source in M87 have led to the first measurement of the size of a black-hole shadow. This observation offers a new and clean gravitational test of the black-hole metric in…
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…
The first images of black hole shadows open new possibilities to constrain modern extended gravity theories. We present the method of shadow background calculation for black hole solutions in the form of Taylor series where $g_{11} = -…
Recent developments in the field of gravitational physics, including the emergence of gravitational wave astronomy, black hole images, and more accurate telescopes, have allowed us to probe the strong-field character of gravity in a novel…
The study of astrophysical phenomena like black hole shadows is an effective approach to properly understand the modified gravity and explore its validity. Motivated by recent astrophysical observations, we consider a black hole (BH) in…
We study gravitational lensing in strong-field limit by a static spherically symmetric black hole in quartic scalar field Horndeski gravity having additional hair parameter $q$, evading the no-hair theorem. We find an increase in the…
Adopting the strong field limit approach, we investigated the strong gravitational lensing in a Brane-World black hole, which means that the strong field limit coefficients and the deflection angle in this gravitational field are obtained.…
The horizon-scale images of supermassive black holes (BHs) by the Event Horizon Telescope Collaboration (EHT) have provided new opportunities to test general relativity and other theories of gravity. In view of future projects, such as the…
We investigate the observational signatures of a quantum-corrected Reissner-Nordstr\"om (RN) black hole to constrain Planck-scale modifications to spacetime geometry using current astrophysical data. By analyzing the null geodesic…
Quadratic gravity constitutes a prototypical example of a perturbatively renormalizable quantum theory of the gravitational interactions. In this work, we construct the associated phase space of static, spherically symmetric, and…
In this work, gravitational lensing in the weak and strong field limits is investigated for black hole spacetime within the framework of Hu-Sawicki $f(R)$ gravity. We employ the Ishihara et al. approach for weak lensing and adopt Bozza's…
Using effective field theory techniques, we compute quantum corrections to spherically symmetric solutions of Einstein's gravity and focus in particular on the Schwarzschild black hole. Quantum modifications are covariantly encoded in a…
Neutron stars and black holes are the astrophysical systems with the strongest gravitational fields in the universe. In this article, I review the prospect of probing with observations of such compact objects some of the most intriguing…
In this paper, we re-examine charged Q-clouds around spherically symmetric, static black holes. In particular, we demonstrate that for fixed coupling constants two different branches of charged scalar clouds exist around Schwarzschild black…
Testing gravity theory in the strong field region becomes a reality due to the observations of gravitational waves and black hole shadows. In this paper, we discuss how to constrain the possible deviations of the classical general…
In this work, we investigate the signatures of black holes within an effective quantum gravity framework recently proposed in the literature [1] . We begin by outlining the general setup, highlighting the two distinct models under…
Under the assumption that a UV theory does not display superluminal behavior, we ask what constraints on superluminality are satisfied in the effective field theory (EFT). We study two examples of effective theories: quantum electrodynamics…
In this paper, we investigate the strong gravitational lensing by the stationary, axially-symmetric black hole in Kerr-Taub-NUT spacetime in the strong field limit. The deflection angle of light ray and other strong deflection limit…