We suggest a simple model to study the problem of the black hole production in particle collisions. The cross-section for the classical and quantum production is analysed within this model. In particular, the possibility to form a black hole in collision of low energy particles (or at large impact parameter) via the quantum tunneling mechanism is pointed out. It is found that, in this model, th...

We study two Schwarzschild black holes as the spherically symmetric solution to the zero mode effective action in the dilatonic domain wall model. This corresponds to the dilatonic version of the Randall-Sundrum(RS) model. Further this can be reduced to the Brans-Dicke(BD) model with the potential, which leads to the RS black hole. In the absence of the potential, one finds the known BD black h...

Accurate prediction of sediment scour hole dimensions downstream of hydraulic structures, e.g. the outlet bucket, is a complex and not straight forward engineering problem encountered worldwide. Because of the complexities of the study, its comprehensive, simultaneous including water flow,  sediment and applying all of the effective variables involved in scouring it is not easy possible. Dimens...

In recent years, Susskind, Thorlacius and Uglum have proposed the model for strings near a black hole horizon in order to represent the quantum mechanical entropy of the black hole and to solve the information loss problem. But, this model is insufficient because they did not consider the metric modification by massive strings and did not explain how to bring out the information from the inside...

A computer simulation is used to investigate hole formation in a model membrane. The model parameters are the stress applied to the membrane, and the edge energy per unit length along the hole boundary (edge tension). Even at zero stress, the membrane has an entropically driven instability against hole formation. Within the model, the minimum edge tension required for the stability of a typical...

Hole concentration and mobility were investigated by Hall measurements in nominally undoped p-type GaSb in the temperature range from 77 to 300 K. The dependence of the thermal ionization energy of native acceptors on the acceptor centre concentration and on the compensation degree was determined. The temperature dependence of the hole mobility was analyzed using a heuristic semi-empirical mode...

We develop a simple physical model to describe the most common type of lowfrequency quasi-periodic oscillations (QPOs) seen in a number of accreting black hole systems, as well as the shape of the relativistically broadened iron emission lines that often appear simultaneously in such sources. The model is based on an inclined ring of hot gas that orbits the black hole along geodesic trajectorie...

I consider a toy model of self-regulated black hole accretion. The black hole grows through Bondi accretion and a fraction of the accretion power is distributed as thermal feedback into the surrounding gas. The gas expands or contracts until AGN heating and radiative cooling balance each other. The balance of heating and cooling is used to determine a quasi-equilibrium temperature at which the ...