It is widely agreed upon that AGN and Quasars are driven by gas accretion onto a supermassive black hole. The origin of the latter however still remains an open question. In this work we present the results of an extremely simple cosmological model combined with an evolutionary scenario in which both the formation of the black hole as well as the gas accretion onto it are triggered by major mer...

Building upon our previous work on two-dimensional stringy black holes and its extension to spherically-symmetric four-dimensional stringy black holes, we show how the latter retain information. A key rôle is played by an infinite-dimensional W∞ symmetry that preserves the area of an isolated black-hole horizon and hence its entropy. The exactly-marginal conformal worldsheet operator representi...

Supermassive black holes in the centers of giant elliptical galaxies are remarkably faint given their expected accretion rates. This motivates models of radiatively inefficient accretion, due to either thermal decoupling of ions from electrons, the generation of outflows or convective motions that inhibit accretion, or the settling of gas to a gravitationally unstable disk that forms stars in p...

We study the long term evolution of a solar type star that is being disrupted by a super massive (10 M⊙) black hole. The evolution is followed from the disruption event, which turns the star into a long thin stream of gas, to the point where some of this gas returns to pericenter and begins its second orbit around the black hole. Following the evolution for this long allows us to determine the ...

A 65-year-old lady presented with decreased vision in left eye since seven months. Vision was 6/9 in right eye and 6/36 in left. Examination revealed idiopathic, full-thickness macular hole in left eye; confirmed by optical coherence tomography (OCT). Patient underwent phacoemulsification with intraocular lens (IOL) implantation, vitrectomy, internal limiting membrane (ILM) peeling and 14% C ₃ ...

Black holes are most often detected by the radiation produced when they gravitationally pull in surrounding gas, in a process called accretion. The efficiency with which the hot gas radiates its thermal energy strongly influences the geometry and dynamics of the accretion flow. Both radiatively efficient thin disks and radiatively inefficient thick disks are observed. When the accreting gas get...

This paper describes curtain airbag gas delivery system development work using CFD analysis. The objective of developing gas delivery system was to achieve uniform inflation and reasonable time to position for oblique pole test with 5 %ile female. CFD analysis has been conducted to design gas delivery system of 3 row curtain airbag. The gas delivery system consists of T-diffuser and flexible ga...

A massive black hole exists in almost every galaxy. They occasionally radiate a vast amount of light by releasing gravitational energy accreting gas, with cumulative active period only few $10^8$ years, so-called the duty cycle Active Galactic Nuclei. Namely, many galaxies today host starving hole. Although galaxy collisions have been thought to enhance nucleus activity, origin cycle, especiall...

Abstract In four dimensional general relativity, the fact that a Killing vector in a vacuum spacetime serves as a vector potential for a test Maxwell field provides one with an elegant way of describing the behaviour of electromagnetic fields near a rotating Kerr black hole immersed in a uniform magnetic field. We use a similar approach to examine the case of a five dimensional rotating black h...