Jeans for Genes
نویسندگان
چکیده
منابع مشابه
The Jeans Mechanism and Bulk-viscosity Effects
In this paper we study the gravitational instability in presence of viscosity. In particular, the standard Jeans Mechanism is analyzed taking into account bulk-viscosity effects in the first-order Newtonian dynamics. We show how the perturbation evolution is damped by dissipative processes and the top-down fragmentation mechanism is suppressed for strong viscous effects. The critical value of t...
متن کاملJeans’ gravitational instability and nonextensive kinetic theory
The concept of Jeans gravitational instability is rediscussed in the framework of nonextensive statistics and its associated kinetic theory. A simple analytical formula generalizing the Jeans criterion is derived by assuming that the unperturbed self-gravitating collisionless gas is kinetically described by the q-parameterized class of power law velocity distributions. It is found that the crit...
متن کاملJeans type instability for a chemotactic model of cellular aggregation
We consider an inertial model of chemotactic aggregation generalizing the Keller-Segel model and we study the linear dynamical stability of an infinite and homogeneous distribution of cells (bacteria, amoebae, endothelial cells,...) when inertial effects are accounted for. These inertial terms model cells directional persistance. We determine the condition of instability and the growth rate of ...
متن کاملRelaxation, the Boltzmann-Jeans conjecture, and chaos.
Slow (logarithmic) relaxation from a highly excited state is studied in a Hamiltonian system with many degrees of freedom. The relaxation time is shown to increase as the exponential of the square root of the energy of excitation, in agreement with the Boltzmann-Jeans conjecture, while it is found to be inversely proportional to residual Kolmogorov-Sinai entropy, introduced in this Rapid Commun...
متن کاملDark matter density profiles from the Jeans equation
We make a simple analytical study of radial profiles of dark matter structures, with special attention to the question of the central radial density profile. We let our theoretical assumptions be guided by results from numerical simulations, and show that at any radius where both the radial density profile, ρ, and the phase-space-like density profile, ρ/σǫ, are exact power laws, the only allowe...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Biochemist
سال: 2013
ISSN: 0954-982X,1740-1194
DOI: 10.1042/bio03503054