Results 31 to 40 of about 519,784 (286)
Mathematical Formalism in Cosmological Models of Gravity
Semina: Ciências Exatas e Tecnológicas, 2016 We analyze solutions to Friedmann-Robertson-Walker cosmologies in Brans-Dicke theory, where a scalar field is coupled to gravity. The cosmological solutions of Brans-Dicke theory, characterized by a decaying vacuum energy density and by a constant ...
Artigo Retratado
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Quantum cosmological perfect fluid model and its classical analogue [PDF]
, 2001 The quantization of gravity coupled to a perfect fluid model leads to a Schr\"odinger-like equation, where the matter variable plays the role of time. The wave function can be determined, in the flat case, for an arbitrary barotropic equation of state $p
A. B. Batista +13 more
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Conformal Einstein Perfect Fluid Spacetimes [PDF]
Journal of Physics: Conference Series, 2011 A review is given of results obtained in connection with perfect fluid spacetimes which are conformally related to Einstein spaces.
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Gradient Ricci Bourguignon solitons on perfect fluid space-times [PDF]
Journal of Mahani Mathematical ResearchThe main purpose of the present paper is about characterizing the properties of the perfect fluid space-time that admits the gradient Ricci-Bourguignon soliton. This gives some results about the stability of the energy-momentum tensor and also under some
Sakineh Hajiaghasi, Shahroud Azami
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Similarity of Solutions of Non Conformally Perfect Fluid Models of Embedding Class One [PDF]
Engineering and Technology Journal, 2013 The Study of similarity Transformation Method has played a remarkable role of dealing with many immediate theoretical and practical applications in our life problems, such as physical and engineering problems [6].This method find the solution for the ...
Dhuha Majeed Salih
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Results in Physics, 2021 Static spaces (with perfect fluids) appeared in a natural way both in physics (cf. Hawking and Ellis, 1975) and mathematics (cf. A. Fischer and J. Marsden, Duke Math. J. 42 (3) (1975), 519–547).
Ibrahim Al-Dayel +2 more
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Gravitational field of a spherical perfect fluid
European Physical Journal C: Particles and Fields, 2019 Analyzing the spacetime for a static spherically distributed perfect fluid we show that the smooth matching of the interior and exterior metrics for a realistic source is possible only for the distances from the origin that exceeds the photon sphere ...
Merab Gogberashvili, Beka Modrekiladze
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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
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Fluid dynamics in the warp drive spacetime geometry
European Physical Journal C: Particles and Fields, 2021 The Alcubierre warp drive metric is a spacetime geometry featuring a spacetime distortion, called a warp bubble, where a massive particle inside it acquires global superluminal velocities, or warp speeds.
Osvaldo L. Santos-Pereira +2 more
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Kinematic Self-Similar Cylindrically Symmetric Solutions
, 2005 This paper is devoted to find out cylindrically symmetric kinematic self-similar perfect fluid and dust solutions. We study the cylindrically symmetric solutions which admit kinematic self-similar vectors of second, zeroth and infinite kinds, not only ...
Carr B. J. +7 more
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