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Related papers: Cosmological Two-stream Instability

200 papers

This paper addresses the stability of plane Couette flow in the presence of strong density and viscosity stratifications. It demonstrates the existence of a generalised inflection point that satisfies the generalised Fjortoft's criterion of…

Fluid Dynamics · Physics 2024-06-13 B. Bugeat , P. C. Boldini , A. M. Hasan , R. Pecnik

Many fluid-dynamical systems met in nature are quasi-two-dimensional: they are constrained to evolve in approximately two dimensions with little or no variation along the third direction. This has a drastic effect in the flow evolution…

Fluid Dynamics · Physics 2024-11-14 Alexandros Alexakis

In conventional fluid mechanics, the chemical composition and thermodynamic state of a fluid-solid interface are not considered when establishing velocity-field boundary conditions. As a consequence, fluid simulations are usually not able…

Particles in pressure-driven channel flow are often inhomogeneously distributed. Two modes of low-Reynolds number instability, absent in Poiseuille flow of clean fluid, are created by inhomogeneous particle loading, and their mechanism is…

Fluid Dynamics · Physics 2024-11-27 Anup Kumar , Rama Govindarajan

We explore the phenomenology of a two-fluid cosmological model, where the field equations of general relativity (GR) are sourced by baryonic and cold dark matter. We find that the model allows for a unified description of small and large…

General Relativity and Quantum Cosmology · Physics 2021-07-07 Mariano Cadoni , Andrea P. Sanna

A five-dimensional cosmological model including a single perfect fluid is studied in the framework of dynamical system analysis. All the critical points of the system with their stability properties are listed and some representative phase…

General Relativity and Quantum Cosmology · Physics 2020-02-17 A. Savaş Arapoğlu , Ezgi Canay , A. Emrah Yükselci

We study the two-phase Stokes flow driven by surface tension with two fluids of equal viscosity, separated by an asymptotically flat interface with graph geometry. The flow is assumed to be two-dimensional with the fluids filling the entire…

Analysis of PDEs · Mathematics 2024-04-26 Bogdan-Vasile Matioc , Georg Prokert

Cosmological perturbation equations derived from low-energy effective actions are shown to be invariant under a duality transformation reminiscent of electric-magnetic, strong-weak coupling, S-duality. A manifestly duality-invariant…

High Energy Physics - Theory · Physics 2009-10-31 R. Brustein , M. Gasperini , G. Veneziano

Topological defects are thought to be left behind by the cosmological phase transitions which occur as the universe expands and cools. Similar processes can be studied in the phase transitions which take place in the laboratory:…

Condensed Matter · Physics 2014-10-13 Wojciech Hubert Zurek

The interface between an unstable state and a stable state usually develops a single confined front travelling with constant velocity into the unstable state. Recently, the splitting of such an interface into {\em two} fronts propagating…

patt-sol · Physics 2009-10-22 F. J. Elmer , J. -P. Eckmann , G. Hartsleben

A pair of concentric spheres separated by a small gap form a spherical Hele-Shaw cell. In this cell an interfacial instability arises when two immiscible fluids flow. We derive the equation of motion for the interface perturbation…

Soft Condensed Matter · Physics 2009-10-31 Jose A. Miranda , Fernando Parisio , Fernando Moraes , Michael Widom

My goal is to study the dynamics of the Universe from a relational perspective based on the happening of events in temporal relation to each other and their respective points of reference. Accordingly, the flow of time was modeled as the…

General Physics · Physics 2025-05-13 Bruce M Boman

The instability of a monoenergetic electron beam in a collisional one-dimensional plasma bounded between grounded walls is considered both analytically and numerically. Collisions between electrons and neutrals are accounted for the plasma…

Plasma Physics · Physics 2017-01-04 Dmytro Sydorenko , Igor D. Kaganovich , Peter L. G. Vetzek

The linear stability of stratified two-phase flows in rectangular ducts is studied numerically. The linear stability analysis takes into account all possible infinitesimal three-dimensional disturbances and is carried out by solution of the…

Fluid Dynamics · Physics 2020-04-09 Alexander Gelfgat , Neima Brauner

The boundary conditions prescribing the constant traction or the so-called do-nothing conditions are frequently taken on artificial boundaries in the numerical simulations of steady flow of incompressible fluids, despite the fact that they…

Fluid Dynamics · Physics 2020-02-25 M. Lanzendörfer , J. Hron

We show that in tilting perfect fluid cosmological models with an ultra-radiative equation of state, generically the tilt becomes extreme at late times and, as the tilt instability sets in, observers moving with the tilting fluid will…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. A. Coley , S. Hervik , W. C. Lim

In this paper, we discuss the dynamics of two- scalar-field cosmological models. Unlike in the situation of exponential potential, we find that there are late-time attractors in which one scalar field dominates the energy density of…

General Relativity and Quantum Cosmology · Physics 2017-11-09 Yu Li

Flow instabilities play important roles in a wide range of engineering, geophysical, and astrophysical flows, ranging from supernova explosion in crab nebula, formation of clouds in sky, waves on ocean, to inertial confinement fusion…

Fluid Dynamics · Physics 2024-06-06 Wei Li

We show that there is a correspondence between cosmology from non-extensive thermodynamics and cosmology with fluids of redefined and generalized equation of state. We first establish the correspondence in the case of basic non-extensive…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Shin'ichi Nojiri , Sergei D. Odintsov , Emmanuel N. Saridakis , R. Myrzakulov

New plasma mechanism for the generation of toroidal magnetic field in the magnetosphere of Crab pulsar is presented. It is based on the development of two-stream instability in the relativistic electron-positron plasma of the pulsar…

Astrophysics of Galaxies · Physics 2011-10-04 Irakli S. Nanobashvili