166 citations · 542 across the 24 of their papers we have counts for
14 papers · 1 filter
Modeling a Maunder Minimum
A. Brandenburg, E. A. Spiegel
We introduce on/off intermittency into a mean field dynamo model by imposing stochastic fluctuations in either the alpha effect or through the inclusion of a fluctuating electromot…
Continuum Equations for Stellar Dynamics
Edward A. Spiegel, Jean-Luc Thiffeault
The description of a stellar system as a continuous fluid represents a convenient first approximation to stellar dynamics, and its derivation from the kinetic theory is standard. T…
Luminosity Effects in Projected Fractals
R. Thieberger, E. A. Spiegel
We analyze examples of projected two dimensional fractals for the case where the objects studied have a Schechter luminosity function. Our results indicate that two dimensional cat…
Shear and Mixing in Oscillatory Doubly Diffusive Convection
Francesco Paparella, Edward A. Spiegel, Suzanne Talon
To investigate the mechanism of mixing in oscillatory doubly diffusive (ODD) convection, we truncate the horizontal modal expansion of the Boussinesq equations to obtain a simplifi…
A Continuum Description of Rarefied Gas Dynamics (III)--- The Structures of Shock Waves
Xinzhong Chen, Hongling Rao, Edward A. Spiegel
We use the one-dimensional steady version of the equations derived in paper I to compute the structure of shock waves. The agreement with experiment is good, especially when we ret…
The Radiative Stress Tensor
Xinzhong Chen, Edward A. Spiegel
We use the transfer equation in relativistic form to develop an expansion of the one-photon distribution for a medium with constant photon mean free path, . The resulting radiat…
Photofluid Instabilities of Hot Stellar Envelopes
Edward A. Spiegel, Louis Tao
Beginning from a relatively simple set of dynamical equations for a fluid permeated by a radiative field strong enough to produce significant forces, we find the structure of plane…
Particle Aggregation in a turbulent Keplerian flow
A. Bracco, P. H. Chavanis, A. Provenzale +1
In the problem of planetary formation one seeks a mechanism to gather small solid particles together into larger accumulations of solid matter. Here we describe a scenario in which…
Scaling Regimes in the Distribution of Galaxies
G. Murante, A. Provenzale, E. A. Spiegel +1
If we treat the galaxies in published redshift catalogues as point sets, we may determine the generalized dimensions of such sets by standard means, outlined here. For galaxy separ…
Negative Energy Modes and Gravitational Instability of Interpenetrating Fluids
A. R. R. Casti, P. J. Morrison, E. A. Spiegel
We study the longitudinal instabilities of two interpenetrating fluids interacting only through gravity. When one of the constituents is of relatively low density, it is possible t…
Stellar Oscillons
O. M. Umurhan, L. Tao, E. A. Spiegel
We study the weakly nonlinear evolution of acoustic instability of a plane- parallel polytrope with thermal dissipation in the form of Newton's law of cooling. The most unstable ho…
Spotted Disks
A. Bracco, A. Provenzale, E. A. Spiegel +1
Rotating, turbulent cosmic fluids are generally pervaded by coherent structures such as vortices and magnetic flux tubes. The formation of such structures is a robust property of r…
Gravitational Screening
Edward A. Spiegel
Calculations of the stopping power of a medium lead to divergent integrals in gravitational theory as they do in the analogous electromagnetic problem. In the em case, one introduc…
Density Singularities and Cosmic Structures
G. Murante, A. Provenzale, E. A. Spiegel +1
We show that an array of singular density concentrations accounts for the scaling exponents observed in the luminous matter distribution in the Universe for scales below 10Mpc. Thi…