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Related papers: Analog gravity in nonisentropic fluids

200 papers

Astrophysical compact objects are usually studied using a perfect fluid model. However, in astrophysical processes out-of-equilibrium, dissipative effects become important to describe the dynamics of the system. In this work, we obtain…

General Relativity and Quantum Cosmology · Physics 2025-08-05 David Díaz-Guerra , Conrado Albertus , Prasanta Char , M. Ángeles Pérez-García

Understanding the non-adiabatic pressure, or relative entropy, perturbation is crucial for studies of early-universe vorticity and Cosmic Microwave Background observations. We calculate the evolution of the linear non-adiabatic pressure…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Iain A. Brown , Adam J. Christopherson , Karim A. Malik

Nonmagnetic and spherically symmetric dielectric material media are investigated in their generality as analogue models, in the domains of geometrical optics, for a few relevant static and spherically symmetric solutions of gravitation,…

General Relativity and Quantum Cosmology · Physics 2021-10-29 Eduardo Bittencourt , Diego Renan Da Silva , Érico Goulart , Renato Klippert

The irreducible representations of the extended Galilean group are used to derive the symmetric and asymmetric wave equations. It is shown that among these equations only a new asymmetric wave equation is fundamental. By being fundamental…

Classical Physics · Physics 2023-04-17 Z. E. Musielak

In space plasma, various effects of magnetic reconnection and turbulence cause the electron motion to significantly deviate from their Larmor orbits. Collectively these orbits affect the electron velocity distribution function and lead to…

Plasma Physics · Physics 2018-04-04 H. Che , C. Schiff , G. Le , J. Dorelli , B. Giles , T. Moore

We here study extended classes of logotropic fluids as \textit{unified dark energy models}. Under the hypothesis of the Anton-Schmidt scenario, we consider the universe obeying a single fluid whose pressure evolves through a logarithmic…

General Relativity and Quantum Cosmology · Physics 2019-04-16 Kuantay Boshkayev , Rocco D'Agostino , Orlando Luongo

Understanding out-of-equilibrium quantum dynamics is a critical outstanding problem, with key questions regarding characterizing adiabaticity for applications in quantum technologies. We show how the metric-space approach to quantum…

Quantum Physics · Physics 2018-07-11 A. H. Skelt , R. W. Godby , I. D'Amico

Anisotropic magneto resistances and intrinsic adiabatic transport features are generated on quantum Hall samples based on an (Al,Ga)As/GaAs heterostructure with alloyed Au/Ge/Ni contacts. We succeed to probe the microscopic origin of these…

Mesoscale and Nanoscale Physics · Physics 2015-05-18 F. Dahlem , E. Ahlswede , J. Weis , K. v. Klitzing

Except for the presence of gravitational wave source term, the relativistic perturbation equations of a zero-pressure irrotational fluid in a flat Friedmann world model coincide exactly with the Newtonian ones to the second order in…

Astrophysics · Physics 2009-11-11 J. Hwang , H. Noh

By constructing a hydrodynamic canonical formalism, we show that the occurrence of an arbitrary density-dependent gauge potential in the meanfield Hamiltonian of a Bose-condensed fluid invariably leads to nonlinear flow-dependent terms in…

Quantum Gases · Physics 2021-01-06 Y. Buggy , L. G. Phillips , P. Öhberg

Motivated by the need to conceive freely-precessing gyroscopes for detecting acoustic frame-dragging predicted recently in rotating acoustic analogue black holes, we report an incipient investigation on the hydrodynamics of nematic active…

General Relativity and Quantum Cosmology · Physics 2018-08-14 Amitava Banerjee , Ratna Koley , Parthasarathi Majumdar

For flows of a lossless gas, the stagnation enthalpy obeys a linear convected wave equation with coefficients which depend on the flow variables. This equation is self-adjoint and one has a reciprocity relation between source and observer.…

Fluid Dynamics · Physics 2010-09-21 Willi Mohring

Inviscid hydrodynamics mediates forces through pressure and other, typically irrotational, external forces. Acoustically induced forces must be consistent with arising from such a pressure field. The use of "acoustic stress" is shown to…

Fluid Dynamics · Physics 2014-09-30 Clifford Chafin

Several misprints and small mistakes were in the initial version. They have been corrected. Following the recent experimental realization of synthetic gauge magnetic forces, Jean Dalibard adressed the question whether the adiabatic ansatz…

Analysis of PDEs · Mathematics 2012-01-24 Amandine Aftalion , Francis Nier

We consider non-linear gravitational models with a multidimensional warped product geometry. Particular attention is payed to models with quadratic scalar curvature terms. It is shown that for certain parameter ranges, the extra dimensions…

High Energy Physics - Theory · Physics 2014-11-18 U. Guenther , P. Moniz , A. Zhuk

This paper is the second in a sequence of three devoted to the formulation of a theory of self-gravitating anisotropic fluids in both Newtonian gravity and general relativity. In this second paper we develop the Newtonian theory, inspired…

General Relativity and Quantum Cosmology · Physics 2024-06-06 Tom Cadogan , Eric Poisson

The nonanalytic property of metric resulting from the presence of gravitomagnetic monopoles is considered. The curvature tensors, dual curvature tensors, dual Einstein tensor (and hence the gravitational field equation of gravitomagnetic…

General Relativity and Quantum Cosmology · Physics 2009-09-01 Jian Qi Shen

A Lagrangian formalism is developed for a general nondissipative quasiperiodic nonlinear wave with trapped particles in collisionless plasma. The adiabatic time-averaged Lagrangian density $\mcc{L}$ is expressed in terms of the…

Plasma Physics · Physics 2015-05-28 I. Y. Dodin , N. J. Fisch

In this paper, we have studied gravitational collapse and expansion of non-static anisotropic fluid in $5D$ Einstein Gauss-Bonnet gravity. For this purpose, the field equations have been modeled and evaluated for the given source and…

General Relativity and Quantum Cosmology · Physics 2018-12-19 G. Abbas , M. Tahir

The selfgravity of an infalling gas can alter significantly the accretion of gases. In the case of spherically symmetric steady flows of polytropic perfect fluids the mass accretion rate achieves maximal value when the mass of the fluid is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Bogusz Kinasiewicz , Patryk Mach , Edward Malec