Results 31 to 40 of about 7,610 (173)
Thermodynamics of magnetized binary compact objects [PDF]
, 2010 Binary systems of compact objects with electromagnetic field are modeled by helically symmetric Einstein-Maxwell spacetimes with charged and magnetized perfect fluids. Previously derived thermodynamic laws for helically-symmetric perfect-fluid spacetimes
Gourgoulhon, Eric +2 more
core +2 more sources
No Go Theorem for Kinematic Self-Similarity with A Polytropic Equation of State [PDF]
, 2002 We have investigated spherically symmetric spacetimes which contain a perfect fluid obeying the polytropic equation of state and admit a kinematic self-similar vector of the second kind which is neither parallel nor orthogonal to the fluid flow.
A. Ori +28 more
core +2 more sources
Flat holography and Carrollian fluids
Journal of High Energy Physics, 2018 We show that a holographic description of four-dimensional asymptotically locally flat spacetimes is reached smoothly from the zero-cosmological-constant limit of anti-de Sitter holography.
Luca Ciambelli +4 more
doaj +1 more source
New symmetry for the imperfect fluid
European Physical Journal C: Particles and Fields, 2020 We will address the existence of a new symmetry for an imperfect fluid by introducing local four-velocity gauge-like transformations for the case when there is vorticity.
Alcides Garat
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Non-relativistic gravity and its coupling to matter
Journal of High Energy Physics, 2020 We study the non-relativistic expansion of general relativity coupled to matter. This is done by expanding the metric and matter fields analytically in powers of 1/c 2 where c is the speed of light.
Dennis Hansen +2 more
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Stability of generic thin shells in conformally flat spacetimes
European Physical Journal C: Particles and Fields, 2017 Some important spacetimes are conformally flat; examples are the Robertson–Walker cosmological metric, the Einstein–de Sitter spacetime, and the Levi-Civita–Bertotti–Robinson and Mannheim metrics.
Z. Amirabi
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A class of higher-dimensional solutions of Einstein’s vacuum equation
European Physical Journal C: Particles and Fields, 2019 A new class of higher-dimensional exact solutions of Einstein’s vacuum equation is presented. These metrics are written in terms of the exponential of a symmetric matrix and when this matrix is diagonal the solution reduces to higher-dimensional ...
Gabriel Luz Almeida, Carlos Batista
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Effects of Electromagnetic Field on Gravitational Collapse
, 2009 In this paper, the effect of electromagnetic field has been investigated on the spherically symmetric collapse with the perfect fluid in the presence of positive cosmological constant.
G. ABBAS +5 more
core +1 more source
Perfect Fluid Spacetimes Admitting Almost Riemann Solitons
AxiomsIn this investigation, we examine the geometric character of almost Riemann solitons and gradient almost Riemann solitons in the context of perfect fluid solutions of the Einstein equations that admit a torse-forming vector field ζ.
Mehdi Jafari, Shahroud Azami
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The Gibbs Paradox, the Landauer Principle and the Irreversibility Associated with Tilted Observers
Entropy, 2017 It is well known that, in the context of General Relativity, some spacetimes, when described by a congruence of comoving observers, may consist of a distribution of a perfect (non–dissipative) fluid, whereas the same spacetime as seen by a “tilted ...
Luis Herrera
doaj +1 more source