A possible violation of the weak gravity conjecture (WGC) by cosmic censorship is one of the
major challenges in the field of general relativity. The cosmic censorship is a fundamental …

A generation method of new metric in the case of static spherically symmetric space-time is
derived. Using this approach, we construct a metric which describes Euler–Heisenberg …

The dark matter halo has non-negligible effects on the gravitational lensing of supermassive
black hole in the galaxy center. Our work presents a study on the time-delay of light in …

Dark matter and dark energy dominate the behavior of our universe. The dark matter usually
forms halo structures in large number of galaxies. Properties of dark matter halo can be …

We examine the thin accretion disk behaviors surrounding black holes embedded in cold
dark matter halos and scalar field dark matter halos. We first calculate the event horizons …

We study thin accretion disks in the gravitational field of a class of rotating regular black
holes. Our objective is to determine the key parameters governing these accretion disks: the …

A bstract The Johannsen black hole (BH) is a generic rotating BH admitting three constants
of motions (energy, angular momentum, and Carter constant) and is characterized by four …

We examine a spherically-symmetric class of spacetimes carrying vacuum energy, while
considering the influence of an external dark energy environment represented by a non …

Current observations show that a significant fraction of the Universe is composed of dark
energy and dark matter. In this paper, the simultaneous effects of these dark sectors on the …

This manuscript investigates a Schwarzschild black hole surrounded by perfect fluid dark
matter embedded in a cloud of strings. The effects of its surroundings on thermodynamics …