Related papers: Fractal features in accretion discs
Fractals are geometric shapes that can display complex and self-similar patterns found in nature (e.g., clouds and plants). Recent works in visual recognition have leveraged this property to create random fractal images for model…
Multifractal properties of a tracer density passively advected by a compressible random velocity field are characterized. A relationship is established between the statistical properties of mass on the dynamical fractal attractor towards…
Using mathematical formalism borrowed from dynamical systems theory, a complete analytical investigation of the critical behaviour of the stationary flow configuration for the low angular momentum axisymmetric black hole accretion provides…
The structure of the inner edge of the accretion disk around a black hole can be altered, if the matter inside the marginally stable orbit is magnetically connected to the disk. In this case, a non-zero torque is exerted on its inner edge,…
We report a new type of restoration of macroscopic isotropy (homogenization) in fractals with microscopic anisotropy. The phenomenon is observed in various physical setups, including diffusions, random walks, resistor networks, and Gaussian…
This paper reviews some aspects of one of the major unsolved problems in understanding astrophysical (in particular, accretion) disks: whether the disk interiors may be effectively viscous in spite of the absence of marnetorotational…
A method is proposed for generating compact fractal disordered media, by generalizing the random midpoint displacement algorithm. The obtained structures are invasive stochastic fractals, with the Hurst exponent varying as a continuous…
A self-consistent solution for a thin accretion disk with turbulent convection is presented. The disk viscosity and the convective flux are derived from a physical model for turbulence, and expressed in terms of the local physical…
We present the results of smoothed particle hydrodynamic simulations investigating the evolution and fragmentation of filaments that are accreting from a turbulent medium. We show that the presence of turbulence, and the resulting…
The fractal distribution of charged particles is considered. An example of this distribution is the charged particles that are distributed over fractal. The fractional integrals are used to describe fractal distribution. These integrals are…
Radiative transfer in a relativistic accretion disk wind is examined under the plane-parallel approximation in the fully special relativistic treatment. For an equilibrium flow, where the flow speed and the source function are constant, the…
The boundaries of central place models proved to be fractal lines, which compose fractal texture of central place networks. A textural fractal can be employed to explain the scale-free property of regional boundaries such as border lines,…
We study numerically the spatial properties of relaxation clusters in a two dimensional sandpile automaton with dynamic rules depending stochastically on a parameter p, which models the effects of static friction. In the limiting cases p=1…
Rapid fluctuation with a frequency dependence of $1/f^{\alpha}$ (with $\alpha \simeq 1 - 2$) is characteristic of radiation from black-hole objects. Its origin remains poorly understood. We examine the three-dimensional…
The vertical structure of stationary thin accretion discs is calculated from the energy balance equation with heat generation due to microscopic ion viscosity {\eta} and electron heat conductivity {\kappa}, both depending on temperature. In…
We study the distribution of swimming micro-organisms advected by a model turbulent flow and attracted towards a localised light source through phototaxis. It is shown that particles aggregate along a dynamical attractor with fractal…
The existence of outflow in accretion flows is confirmed by observations and magnetohydrodynamics (MHD) simulations. In this paper, we study outflows of accretion flows in the presence of resistivity and toroidal magnetic field. The…
Analytical treatment of black hole accretion generally presumes the stability of the stationary configuration. Various authors in the past several decades demonstrated the validity of such an assumption for inviscid hydrodynamic flow.…
Edges fractal approach in graphene e Defects density gain a b s t r a c t To optimize the technological development together with energy gain, the crucial materials needs to be tailored in a smart way to benefit a maximum from the…
Some accreting neutron stars and young stars show unexplained episodic flares in the form of quasi-periodic oscillations or recurrent outbursts. In a series of two papers we present new work on an instability that can lead to episodic…