We study the gravitational collapse of a self-gravitating charged scalar-field. Starting with a regular spacetime, we follow the evolution through the formation of an apparent horizon, a Cauchy horizon and a final central singularity. We find a null, weak, mass-inflation singularity along the Cauchy horizon, which is a precursor of a strong, spacelike singularity along the r = 0 hypersurface. T...

A comparison of the buckling analysis of the nanoplate and nanocomposite plate with a central square hole embedded in the Winkler foundation is presented in this article. In order to enhance the mechanical properties of the nanoplate with a central cutout, the uniformly distributed carbon nanotubes (CNTs) are applied through the thickness direction. In order to define the shape function of the ...

The backreaction on black holes due to dragging heavy, rather than test, objects is discussed. As a case study, a regular black Saturn system where the central black hole has vanishing intrinsic angular momentum, J = 0, is considered. It is shown that there is a correlation between the sign of two response functions. One is interpreted as a moment of inertia of the black ring in the black Satur...

Neutralino dark matter may be incompatible with current cold dark matter models with cuspy dark halos, because excessive synchrotron radiation may originate from neutralino annihilations close to the black hole at the galactic center. We report results obtained in [1], to which we refer for further details. The composition of dark matter is one of the major issues in cosmology. A popular candid...

Medium Field Equation (MFE) multivariate public key cryptosystems were broken by High Order Linearization Equation (HOLE) attack. In order to avoid HOLE attack, we proposed an improvement of MFE, Cubic MFE public key encryption scheme. In our construction, multiplications of three second order matrices were used to get a set of cubic polynomials in the central map. Through theoretical analysis ...

We propose a scenario in which massive stars form in a self-gravitating gaseous disc around a supermassive black hole. We analyze the dynamics of a disc forming around a supermassive black hole, in which the angular momentum is transported by turbulence induced by the disc’s self-gravity. We find that once the surface density of the disc exceeds a critical value, the disc fragments into dense c...

We analyze the observed distribution of Eddington ratios (L/LEdd) as a function of supermassive black hole mass for a large sample of nearby galaxies drawn from the Sloan Digital Sky Survey. We demonstrate that there are two distinct regimes of black hole growth in nearby galaxies. The first is associated with galaxies with significant star formation (M∗/SFR ∼ a Hubble time) in their central ki...

We study static black hole solutions in Einstein and Einstein–Gauss–Bonnet gravity with the topology of the product of two spheres,Sn × Sn, in higher dimensions. There is an unusual new feature of the Gauss–Bonnet black hole: the avoidance of a non-central naked singularity prescribes a mass range for the black hole in terms of > 0. For an Einstein–Gauss–Bonnet black hole a limited window of ne...

INTRODUCTION Macular hole is a common and treatable cause of central visual loss. Classic macular hole surgery consists of vitrectomy, posterior vitreous cortex removal and intraocular gas tamponade, but during the past decade focus has especially been on internal limiting membrane (ILM) peeling as adjuvant therapy for increasing closure rates. OBJECTIVE To determine and evaluate anatomical a...

We use medium resolution optical spectra of 3CR radio galaxies to estimate their black hole masses and accretion rates. Black hole masses are found from central stellar velocity dispersions, and accretion rates are derived from narrow emission-line luminosities. The sample covers both Fanaroff-Riley (FR) classes; the more powerful FRIIs and the less powerful FRIs. We find that FRIs and FRIIs se...