Related papers: High-dimensional Schwarzschild black holes in scal…
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 presence of extra dimensions generically modify the spacetime geometry of a rotating black hole, by adding an additional hair, besides the mass $M$ and the angular momentum $J$, known as the `tidal charge' parameter, $\beta$. In a…
In this work we study whether parametrized spherically symmetric black hole solutions in metric theories of gravity can appear to be isospectral when studying perturbations. From a theory agnostic point of view, the test scalar field wave…
We consider massless scalar field perturbations of regular black holes in quasi-topological gravity. After reviewing various regular black hole solutions, we compute the total absorption cross-section and the partial absorption…
Following Sanchez's approach we investigate the effect of scalar mass in the absorption and emission problems of 4d Schwarzschild black hole. The absorption cross sections for arbitrary angular momentum of the scalar field are computed…
We investigate massive scalar perturbations and several characteristics of particle motion in the spacetime of regular black holes arising in four-dimensional quasi-topological gravity. Quasinormal modes are computed using high-order WKB…
The spectra of gravitational waves from black hole evaporation generically peak at frequencies of order the Hawking temperature, making this signal ultra-high frequency for primordial black holes evaporating in the early universe. This…
In this work, we study of massless three-form black hole, where the three-form fields are higher $p$-form gauge fields with $p=3$. These give rise to the Schwarzschild-de Sitter (Sch-dS)-like solution through an effective cosmological…
During the glorious success of the EHT in providing the first image of a black hole, numerous papers have been published about the effect of different astrophysical environments on black hole geometry. Motivated by the work on how…
We compute the quasinormal spectra for scalar, Dirac and electromagnetic perturbations of the Schwarzschild-de Sitter geometry in the framework of scale-dependent gravity, which is one of the current approaches to quantum gravity. Adopting…
We compute the quasinormal frequencies for scalar and electromagnetic perturbations of an improved Schwarzschild geometry in the framework of asymptotically safe gravity, which is one of the approaches to quantum gravity. Adopting the…
With the possibility of testing massive gravity in the context of black hole physics in mind, we consider the radiation produced by a particle plunging from slightly below the innermost stable circular orbit into a Schwarzschild black hole.…
We present a comprehensive study of the quasinormal modes of a new class of nonlocal static and spherically symmetric black hole (BH) solutions within the framework of the revised Deser-Woodard theory of gravity. These solutions are…
One of the most important issues in relativistic astrophysics is to explain the origin mechanisms of (ultra)high energy charged particle components of cosmic rays. Black holes (BHs) being huge reservoirs of (gravitational) energy can be…
We develop a perturbation theory for surfaces confining photons and massive particles in static spherically symmetric spacetimes in terms of two parameters: the mass-to-energy ratio and the deviation of metric functions from a given form,…
This study investigates the effects of higher dimensions on the observable properties of Schwarzschild-Tangherlini black holes, focusing on the photonsphere, shadow radius, deflection angles, and quasinormal modes (QNMs). By extending…
We study scalar and electromagnetic perturbations of a family of nonsingular nonrotating black hole spacetimes that are solutions in a large class of conformally invariant theories of gravity. The effective potential for scalar…
The merger of binary black holes produces a series of decaying oscillations, during which energy is radiated in gravitational waves. The characteristic signal in the ringdown phase can be described by complex oscillation frequencies called…
We obtain the solution of a static spherically symmetric black hole surrounded by a cloud of strings in Rastall gravity and study the influence of the parameter $a$ associated with strings on the event horizon and the Hawking temperature.…
We consider general perturbations of a Schwarzschild black holes in the context of f(R) gravity. A reduced set of frame independent master variables are determined, which obey two closed wave equations - one for the transverse, trace-free…