The non{linear dynamics of self{gravitating collisionless matter with vanishing vorticity is studied in a general relativistic framework, using synchronous and comoving (i.e. Lagrangian) coordinates. Writing the equations in terms of the metric tensor of the spatial sections orthogonal to the uid ow allows an unambiguous expansion in inverse powers of the speed of light. The Newtonian and post{...

A linear stability analysis of a novel electrohydrodynamic Kelvin-Helmholtz system consisting of the superposition of two uniformly rotating dielectric media is presented. The characteristic equation for such an arrangement is derived, which in turn yields a stability criterion for velocity differences of disturbances at a given rotation frequency. The conditions of stability for long and short...

We are investigating numerically the non-linear behavior of a spaceperiodic MHD system with ABC forcing. Most computations are performed for magnetic Reynolds numbers increasing from 0 to 60 and a fixed kinematic Reynolds number, small enough for the trivial solution with a zero magnetic field to be stable to velocity perturbations. At the critical magnetic Reynolds number for the onset of inst...

Infectious diseases that affect their host on a long timescale can regulate the host population dynamics. Here we show that a strong Allee effect can lead to complex dynamics in simple epidemic models. Generally, the Allee effect renders a population bistable, but we also identify conditions for tri- or monostability. Moreover, the disease can destabilize endemic equilibria and induce sustained...

Isoscalar Cooper pairing in isospin asymmetric nuclear matter occurs between states populating two distinct Fermi surfaces, each for neutrons and protons. The transition from a BCS-like to the normal (unpaired) state, as the isospin asymmetry is increased, is intervened by superconducting phases which spontaneously break translational and rotational symmetries. One possibility is the formation ...

Abstract We study the effect of quantum decoherence on inflationary cosmological perturbations. This process might imprint specific observational signatures revealing nature mechanism being related to longstanding issue quantum-to-classical transition fluctuations. Several works have investigated statistical properties primordial In particular, it has been shown that cosmic leads corrections cu...