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81.
Axially symmetric cosmological models with cosmic string source are obtained in a scalar-tensor theory of gravitation proposed
by Saez and Ballester (Phys. Lett. A113, 467, 1985). The models obtained give us axially symmetric geometric (Nambu) string, p-string and Reddy string (Astrophys. Space Sci. 286, 2003b) in Saez-Ballester theory. Some physical properties of the models are also discussed. 相似文献
82.
83.
84.
85.
Bianchi type-IX space-time is considered in the presence of cosmic string source in the frame work of a scalar- tensor theory
of gravitation proposed by Saez and Ballester (Phys. Lett. A 113:467, 1985). Exact cosmological models representing geometric (Nambu) string, p string and baratropic string are discussed in this theory.
Some physical and kinematical properties of the models are also studied. 相似文献
86.
The problem of thermal convection instability of a horizontal layer of magnetized fluid has been studied to occur crystal growing under the effect of horizontal temperature gradient. In the study, the problem has been reduced to an eigen-value problem for a stream function. The dispersion relations for low viscosity fluid and high viscosity fluid respectively have been discussed analytically and some numerical results have been obtained. It is shown that the critical Rayleigh number and other its related constants for low viscosity fluid (i.e., mercury) are much differ than the high viscosity fluid (i.e., glycerol). 相似文献
87.
D. R. K. Reddy 《Astrophysics and Space Science》1987,133(1):189-191
The field equations of the self-creation theory of gravitation proposed by Barber are solved for a vacuum with the aid of a space-time metric of Friedmann. Some physical properties of the solution are discussed. 相似文献
88.
A spatially-homogeneous and anisotropic-cosmological model in a scalar-tensor theory proposed by Sen and Dunn (1971) is obtained when the source of the gravitational field is a perfect fluid with pressure equal to energy density and the metric is of Bianchi type-I. Various physical properties of the model have also been discussed. 相似文献
89.
D. R. K. Reddy 《Astrophysics and Space Science》1987,138(1):121-125
The Einstein field equations for an irrotational perfect fluid with pressurep, equal to energy density are studied when the space-time is conformally flat. The coordinate transformation to co-moving coordinates is discussed. The energy and Hawking-Penrose inequalities are studied. Static and non-static solutions of the field equations are obtained. It is interesting to note that in the static case the only spherically-symmetric conformally flat solution for self-gravitating fluid is simply the empty flat space-time of general relativity. 相似文献
90.
Nonlinear analysis of electrostatic drift Kelvin-Helmholtz instability is performed. It is shown that the analysis leads to the propagation of the weakly nonlinear dispersive waves and the nonlinear behaviour is governed by the nonlinear Burger's equation. 相似文献