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Related papers: Early-Time Stability of Decelerating Shocks

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Collisionless shocks, that is shocks mediated by electromagnetic processes, are customary in space physics and in astrophysics. They are to be found in a great variety of objects and environments: magnetospheric and heliospheric shocks,…

We investigate the stability, nonlinear development and equilibrium structure of vortices in a background shearing Keplerian flow. We make use of high-resolution global two-dimensional compressible hydrodynamic simulations. We introduce the…

Astrophysics · Physics 2009-11-13 G. Bodo , A. Tevzadze , G. Chagelishvili , A. Mignone , P. Rossi , A. Ferrari

The goal of this paper is to prove the existence and stability of shocks for viscous scalar conservation laws with space periodic flux, in the multi-dimensional case. Such a result had been proved by the first author in one space dimension,…

Analysis of PDEs · Mathematics 2016-03-17 Anne-Laure Dalibard , Moon-Jin Kang

In the Universe matter outside of stars and compact objects is mostly composed of collisionless plasma. The interaction of a supersonic plasma flow with an obstacle results in collisionless shocks that are often associated with intense…

Plasma Physics · Physics 2022-05-18 Artem Bohdan , Martin S. Weidl , Paul J. Morris , Martin Pohl

We investigate the evolution of interfaces among phases of the interstellar medium with different temperature. It is found that, for some initial conditions, the dynamical effects related to conductive fronts are very important even if…

Astrophysics · Physics 2009-10-22 Andrea Ferrara , Yuri Shchekinov

This paper discusses new perspectives and approaches to the problem of disk dynamics where, in this study, we focus on the effects of viscous instabilities influenced by boundary effects. The Boussinesq approximation of the viscous large…

Astrophysics · Physics 2009-11-13 O. M. Umurhan , G. Shaviv

An analysis of the gravitational instability in presence of dissipative effects is addressed. In particular, the standard Jeans Mechanism and the generalization in treating the Universe expansion are both analyzed when bulk viscosity…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Nakia Carlevaro , Giovanni Montani

Higher-order scalar-tensor theories having an instantaneous mode do not develop the Ostrogradsky instability even if a seemingly dangerous mode is present. Such theories satisfy only partially the degeneracy conditions that are usually…

General Relativity and Quantum Cosmology · Physics 2024-03-26 Tsutomu Kobayashi , Takashi Hiramatsu

Using complementary numerical approaches at high resolution, we study the late-time behaviour of an inviscid, incompressible two-dimensional flow on the surface of a sphere. Starting from a random initial vorticity field comprised of a…

Fluid Dynamics · Physics 2015-12-08 David G. Dritschel , Wanming Qi , J. B. Marston

We consider the density wave instability of fermionic dipoles aligned by an external field, and moving in equidistant layers at zero temperature. Using a conserving Hartree-Fock approximation, we show that correlations between dipoles in…

Quantum Gases · Physics 2012-10-05 J. K. Block , N. T. Zinner , G. M. Bruun

The problem of the detachment of a sufficiently large flat indenter from a plane adhesive viscoelastic strip of thickness "b" is studied. For any given retraction speed, three different detachment regimes are found: (i) for very small "b"…

Soft Condensed Matter · Physics 2024-04-05 Ali Maghami , Michele Ciavarella , Antonio Papangelo

If one folds a thin viscoelastic sheet under an applied force, a line of plastic deformation is formed which shapes the sheet into an angle. We determine the parameters that define this angle experimentally and show that, no matter how much…

Soft Condensed Matter · Physics 2020-01-22 Kasra Farain

A new so-called `gravitational loss-cone instability' in stellar systems has recently been investigated theoretically in the framework of linear perturbation theory and proved to be potentially important in understanding the physical…

Astrophysics of Galaxies · Physics 2020-01-08 E. V. Polyachenko , P. Berczik , A. Just , I. G. Shukhman

First results from a high-resolution three-dimensional nonlinear numerical study of the kink oscillation are presented. We show in detail the development of a shear instability in an untwisted line-tied magnetic flux tube. The instability…

Astrophysics · Physics 2009-11-13 J. Terradas , J. Andries , M. Goossens , I. Arregui , R. Oliver , J. L. Ballester

Certain steady states of the Vlasov-Poisson system can be characterized as minimizers of an energy-Casimir functional, and this fact implies a nonlinear stability property of such steady states. In previous investigations by Y. Guo and the…

Mathematical Physics · Physics 2009-10-31 Gerhard Rein

The stability properties of inviscid protostellar disks are examined taking into account the Hall effect and buoyancy. Depending on the parameters, different types of instabilities can exist in different regions of disks. In a very low…

Astrophysics · Physics 2016-08-16 V. Urpin , G. Rüdiger

We prove quantitative decay rates for the linearised Vlasov-Poisson system around compactly supported equilibria. More precisely, we prove decay of the gravitational potential induced by the radial dynamics of this system in the presence of…

Analysis of PDEs · Mathematics 2025-05-22 Mahir Hadzic , Matthew Schrecker

Elucidating the interplay of defect and stress at the microscopic level is a fundamental physical problem that has strong connection with materials science. Here, based on the two-dimensional crystal model, we show that the instability mode…

Soft Condensed Matter · Physics 2020-06-19 Zhenwei Yao

Viscoelastic flows transition from steady to time-dependent, chaotic dynamics under critical flow conditions, but the implications of geometric disorder for flow stability in these systems are unknown. Utilizing microfluidics, we flow a…

Fluid Dynamics · Physics 2020-04-29 Derek M. Walkama , Nicolas Waisbord , Jeffrey S. Guasto

Theoretical approaches to earthquake instabilities propose shear dominated instabilities as a source mechanism. Here we take a fresh look at the role of possible volumetric instabilities preceding a shear instability. We investigate the…

Geophysics · Physics 2019-08-06 K. Regenauer-Lieb , M. Hu , C. Schrank