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We numerically study the parametric pumped current when magnetic field is applied both in the adiabatic and non-adiabatic regimes. In particular, we investigate the nature of pumped current for systems with resonance as well as…

Mesoscale and Nanoscale Physics · Physics 2017-01-09 Fuming Xu , Yanxia Xing , Jian Wang

This paper investigates the problem of time-harmonic acoustic scattering in an inhomogeneous medium with a complex topological structure. Specifically, the medium is anisotropic and contains several disjoint sound-soft obstacles. This model…

Mathematical Physics · Physics 2025-09-30 Huaian Diao , Qingle Meng , Zhiying Sun

The conventional approach of embedding an effective acoustic metric for sound motion in a background flat Minkowski space-time, has recently been extended to incorporate more general curved background metrics, which might contain a black…

General Relativity and Quantum Cosmology · Physics 2022-04-14 Kunal Pal , Kuntal Pal , Tapobrata Sarkar

An exact analogy of electromagnetic fields and particles can be found in mechanics of a turbulent ideal fluid with voids. The system is supposed to form a fine dispersion of voids in the fluid. This microscopically discontinuous medium is…

General Physics · Physics 2007-05-23 Valery P. Dmitriyev

In black hole evaporation process, the mass of the hole anti-correlates with the Hawking temperature. This indicates that the smaller holes have higher surface gravity. For analogue Hawking effects, however, the acoustic surface gravity is…

General Relativity and Quantum Cosmology · Physics 2015-06-24 Pratik Tarafdar , Tapas K Das

Acoustic shock and acceleration waves in inhomogeneous fluids are investigated using both analytical and numerical methods. In the context of start-up signaling problems, and based on linear acoustics theory, we study the propagation of…

Fluid Dynamics · Physics 2018-11-13 R. S. Keiffer , P. M. Jordan , I. C. Christov

For (2+2)-dimensional nonholonomic distributions, the physical information contained into a spacetime (pseudo) Riemannian metric can be encoded equivalently into new types of geometric structures and linear connections constructed as…

General Relativity and Quantum Cosmology · Physics 2010-04-08 Sergiu I. Vacaru

Recent experiments showed that standing acoustic waves could be exploited to induce self-propulsion of rigid metallic particles in the direction perpendicular to the acoustic wave. We propose in this paper a physical mechanism for these…

Fluid Dynamics · Physics 2014-10-29 Francois Nadal , Eric Lauga

This work is concerned with the study of fundamental models from nonlinear acoustics. In Part~I, a hierarchy of nonlinear damped wave equations arising in the description of sound propagation in thermoviscous fluids is deduced. In…

Analysis of PDEs · Mathematics 2017-08-22 Barbara Kaltenbacher , Mechthild Thalhammer

Condensed matter systems, such as acoustics in flowing fluids, light in moving dielectrics, or quasiparticles in a moving superfluid, can be used to mimic aspects of general relativity. More precisely these systems (and others) provide…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Matt Visser , Carlos Barcelo , Stefano Liberati

We study the thermodynamics and non-relativistic hydrodynamics of the holographic fluid on a finite cutoff surface in the Gauss-Bonnet gravity. It is shown that the isentropic flow of the fluid is equivalent to a radial component of…

High Energy Physics - Theory · Physics 2012-08-06 Rong-Gen Cai , Li Li , Zhang-Yu Nie , Yun-Long Zhang

Expansion of a locally equilibrated fluid is considered in an anisotropic space-time given by Bianchi type I metric. Starting from isotropic equilibrium phase-space distribution function in the local rest frame, we obtain expressions for…

General Relativity and Quantum Cosmology · Physics 2018-05-08 Ashutosh Dash , Amaresh Jaiswal

By studying some bouncing universe models dominated by a specific class of hydrodynamical fluids, we show that the primordial cosmological perturbations may propagate smoothly through a general relativistic bounce. We also find that the…

High Energy Physics - Theory · Physics 2009-11-10 Patrick Peter , Nelson Pinto-Neto , Diego A. Gonzalez

The equations of motion of lossless compressible nonclassical fluids under the so-called Green--Naghdi theory are considered for two classes of barotropic fluids: (\textit{i}) perfect gases and (\textit{ii}) liquids obeying a quadratic…

Fluid Dynamics · Physics 2016-08-25 Ivan C. Christov

We consider equations describing a barotropic inviscid flow in a channel with topography effects and beta-plane approximation of Coriolis force, in which a large-scale mean flow interacts with smaller scales. Gibbsian measures associated to…

Probability · Mathematics 2022-05-13 Francesco Grotto , Umberto Pappalettera

It is well known that Lagrangian dynamical systems naturally arise in describing wave front dynamics in the limit of short waves (which is called pseudoclassical limit or limit of geometrical optics). Wave fronts are the surfaces of…

Differential Geometry · Mathematics 2007-05-23 Ruslan Sharipov

In conventional \textit{ab initio} methodologies, phonons are calculated by solving equations of motion involving static interatomic force constants and atomic masses. The Born-Oppenheimer approximation, where all electronic degrees of…

Materials Science · Physics 2024-03-15 Shang Ren , John Bonini , Massimiliano Stengel , Cyrus E. Dreyer , David Vanderbilt

We consider applications of the theory of balanced weight filtrations and iterated logarithms, initiated in arXiv:1706.01073, to PDEs. The main result is a complete description of the asymptotics of the Yang--Mills flow on the space of…

Representation Theory · Mathematics 2018-02-13 Fabian Haiden , Ludmil Katzarkov , Maxim Kontsevich , Pranav Pandit

We analyse the gravitational behaviour of a relativistic heat conducting fluid in a shear-free spherically symmetric spacetime. We show that the isotropy of pressure is a consistency condition which realises a second order nonlinear…

General Relativity and Quantum Cosmology · Physics 2015-12-31 B. P. Brassel , S. D. Maharaj , G. Govender

We study the dynamical instability of a spherically symmetric anisotropic fluid which collapses adiabatically under the condition of vanishing expansion scalar. The Newtonian and post Newtonian regimes are considered in detail. It is shown…

General Relativity and Quantum Cosmology · Physics 2012-04-18 L. Herrera , G. Le Denmat , N. O. Santos