arXiv subjects

Pavel M. Lushnikov

Publications and source records attributed to Pavel M. Lushnikov.

40 records · Page 3Linked to original sources

arXiv2004

Exactly Integrable Dynamics of Interface between Ideal Fluid and Light Viscous Fluid

It is shown that dynamics of the interface between ideal fluid and light viscous fluid is exactly integrable in the approximation of small surface slopes for two-dimensional flow. Stokes flow of viscous fluid provides a relation between normal velocity and pressure at interface. Surface elevation and velocity potential of ideal fluid are determined from two complex Burgers equations corresponding to analytical continuation of velocity potential at the interface into upper and lower complex half planes, respectively. The interface loses its smoothness if complex singularities (poles) reach the interface.

physics.flu-dyn↗

arXiv2004

Oscillating tails of dispersion-managed soliton

Oscillating tails of dispersion-managed optical fiber system are studied for strong dispersion map in the framework of path-averaged Gabitov-Turitsyn equation. The small parameter of the analytical theory is the inverse time. An exponential decay in time of soliton tails envelope is consistent with nonlocal nonlinearity of Gabitov-Turitsyn equation, and the fast oscillations are described by a quadratic law. The pre-exponential modification factor is the linear function of time for zero average dispersion and cubic function for nonzero average dispersion.

nlin.PS↗

arXiv2003

Instability Versus Equilibrium Propagation of Laser Beam in Plasma

We obtain, for the first time, an analytic theory of the forward stimulated Brillouin scattering instability of a spatially and temporally incoherent laser beam, that controls the transition between statistical equilibrium and non-equilibrium (unstable) self-focusing regimes of beam propagation. The stability boundary may be used as a comprehensive guide for inertial confinement fusion designs. Well into the stable regime, an analytic expression for the angular diffusion coefficient is obtained, which provides an essential correction to a geometric optic approximation for beam propagation.

physics.plasm-ph↗

arXiv2002

Collapse of Bose-Einstein condensate with dipole-dipole interactions

A dynamics of Bose-Einstein condensate of a gas of bosonic particles with long-range dipole-dipole interactions in a harmonic trap is studied. Sufficient analytical criteria are found both for catastrophic collapse of Bose-Einstein condensate and for long-time condensate existence. Analytical criteria are compared with variational analysis.

cond-mat↗