Results 61 to 70 of about 84,386 (305)
Anisotropic Cosmological Model in a Modified Theory of Gravitation
East European Journal of PhysicsIn this research, spatially homogeneous and anisotropic LRS Bianchi type-I cosmological model in f(R, T) theory is discussed by choosing the specific form as f(R, T) = R + μe-γR + λT, here R is the Ricci scalar, T is the trace of the energy-momentum ...
G. Satyanarayana +5 more
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A Note on the Geometry of RW Space-Times
Mathematics, 2023 A conformally flat GRW space-time is a perfect fluid RW space-time. In this note, we investigated the influence of many differential curvature conditions, such as the existence of recurrent and semi-symmetric curvature tensors.
Sameh Shenawy +2 more
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Field theory of the Eulerian perfect fluid [PDF]
Classical and Quantum Gravity, 2017 Abstract The Eulerian perfect-fluid theory is reformulated from its action principle in a pure field-theoretic manner. Conservation of the convective current is no longer imposed by Lin’s constraints, but rather adopted as the central idea of the theory.
Taketo Ariki, Pablo A Morales
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Advanced Engineering Materials, EarlyView.A simplified thermoplastic pultrusion model is developed to predict thermal fields in glass fiber/polyethylene terephthalate (GF/PET) composites with reduced computational cost. By combining effective material homogenization, validation against literature data, and Gaussian‐process‐based optimization, the study reveals how heating limits, pulling speed,
Elder Soares +3 more
wiley +1 more source
Gravitational Collapse of Inhomogenous Perfect Fluid [PDF]
, 2014 We study the complete gravitational collapse of a class of inhomogeneous perfect fluid models obtained by introducing small radial perturbations in an otherwise homogeneous matter cloud. The key feature that we assume for the perturbation profile is that
Satin, Seema +2 more
core
Generating new perfect fluid solutions from known ones
, 1996 Stationary perfect-fluid configurations of Einstein's theory of gravity are studied. It is assumed that the 4-velocity of the fluid is parallel to the stationary Killing field, and also that the norm and the twist potential of the stationary Killing ...
Rácz, István, Zsigrai, József
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Many Body in General Relativity: A Thermal Equivalence Principle
Quantum ReportsIn this paper, we review the physics of many bodies in the context of general relativity. Starting from the stress–energy tensor for one body and moving onto those for a swarm of bodies and for a perfect fluid, we review the relativistic hydrodynamics ...
Riccardo Fantoni
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Semiconformal curvature tensor and perfect fluid spacetimes in general relativity
Journal of Taibah University for Science, 2020 The semiconformal curvature tensor and its divergence have been studied for perfect fluid spacetimes. It is seen, apart from other results, that the perfect fluid spacetimes with divergence-free semiconformal curvature tensor either satisfy the vacuum ...
Musavvir Ali +2 more
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Static and stationary dark fluid universes: a gravitoelectromagnetic perspective
Scientific Reports, 2022 The usual characterization of exact solutions of Einstein field equations, including cosmological solutions, is based on the symmetry properties of their corresponding metrics which is obviously mathematically involved.
M. Nouri-Zonoz, A. Nourizonoz
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On Variational Principles for Gravitating Perfect Fluids [PDF]
Annals of Physics, 1996 (29 pages, REVTEX) (\end{document} statement has been added. That's all.)
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